Gmt400 to gmt800 brake upgrade. The front brake upgrade was noticeable.
Gmt400 to gmt800 brake upgrade my question is the truck has its 16s replaced with 15s will the nbs calipers and rotors clear? I read on the post that the early ones are 12 inch I think it might barely How much of an upgrade is it using larger 12. This also results in less clamping force at the brakes. Kevco2 My '88 had JB3 brakes--the worst power-assisted brakes ever installed on a GMT400. If you're feeling really froggy, research brake system math, get the specs for each part in the brake system, build a spreadsheet, and buy the parts you want that don't throw the numbers out of spec. 15" drw is 3. Dec 2, 2015 #15 98nightmare Bill. I just bought my first truck, 1998 GMC c1500. Latest: ORVietVet; Tuesday at 11:35 AM; Introduction. Replies 20 Views 2K. 56 degree/2" taper reamer to enlarge the GMT800 knuckle's upper ball joint taper to fit GMT400 balljoint. I've never had any issues or complaints on my GMT800 2006 SIerra Denali brakes, even when towing my RV or loaded car hauler. Reactions: 99xcss4 , Road Trip , 396SS and 1 other person I did this upgrade on my gmt800 and noticed a difference all around, bc i think the factory put bare minimal effort in grounding these trucks. Disc brakes require more pressure and fluid to stop a vehicle. This spring, I installed a Dana 70S rear axle from a Chevy Express van into my GMT400 K2500 Suburban. Once I went to the GMT800 disc/disc setup, the rear discs stopped after 15-20% pedal travel. 5" rotor/4 piston caliper have been adapted to GMT900's and GMT800's already with minimal work. The truck I'm considering has 4wd, 6. Jun 22, 2016 #64 R. Your best bet would be to go to the auto salvage yard and buy a pair of steering knuckles complete with hubs, brake I have been working on a budget "big brake" upgrade for my 93 Burb, consisting of the new 2019+ Silverado 13. Thread starter 99GMT425; I found a hub that bolts to the GMT800 spindles that is 5-lug (although its 5. 5 14 bolt. 18 flavor, and finally a master cyl. Now, the brake pedal is without question firmer. Has anyone tried the brake upgrade using the 2019 and up rotors and four piston calipers? Found this video on it. I've had my share of GMT400's but this one needs a brake My plan is to do a rear disc upgrade from Little Shop MFG (www. Reactions: RichLo. I could simply swap out with another gmt400 master but was curious is I could keep the gmt400 hydrobooster and upgrade the master from a gmt800. The GMT800 brake upgrade is NOT an easy swap on a 2 wheel drive, The gmt800 brakes ARE far superior to the gmt400, but for 2 wheel drive guys, it is not an easy bolt on swap Like it is for 4x4 guys. Your rear brakes will be more likely to lock up, which can result in a spin instead of a straight stop. That said, I have the GMT800 on my truck, and my rear brakes work just fine. 15" diamter piston, and dual rear wheeled trucks used a 3. I bench bled it and installed. Up front you can swap calipers, rotors, and pads to If your truck isn’t a dually, you can easily upgrade to the dually calipers which have a slightly larger piston. The new MC is 1 ¾ shorter, Well supposedly the GMT800 has a 38mm single bore and the single bore GMT400 has a 39mm single bore. The Hydroboost came from a 2005 z71 Suburban (GMT800). Remember that the REAR brakes are going to be different between JB5 and JB/JD7. My truck is a 2000 k2500 8600gvw. Upgrade the rear brakes to the 11. I do So since it’s possible to upgrade the gmt400 to gmt800 As far as brake upgrades, you can use the drw 1 3/16" wheel cylinders in the rear along with the acdelco rear brake shoes. The Dana 70 comes with massive rear disc brakes, but I This is something I also have been doing a lot of research on, and have both a GMT400 complete subframe and a GMT800 subframe Im trying to compare and see what and how to swap over a few pieces. The most popular GMT400 brake upgrades include: GMT400 rear disc brake conversion; GMT800 brakes on GMT400; GMT 400 brake master cylinder upgrade; Fitting NBS GMT800 brakes to an OBS GMT400 seems like a good idea until you start reading enough forum posts about issues that can come up. Anyhow, I did the GMT800 front knuckle/ brake "upgrade" along with the GMT800 master cylinder. The truck used is a 1989 Chevy K1500 Silverado. Convince me, I may be interested. If you swap to GMT800 brakes, you'd better take everything so you still have a "matched set" of components--including the rear brakes. I also thoroughly bled the system with my Motive power bleeder and I am quite certain I got all the air out. Oct 24, 2022 #3 bretcopsey I'm Awesome. What's new. Looks are subjective and I think you're overstating the weight differential between the discs and drums. I just watched this guy swap GMT 800 front brakes into his K2500 suburban. I read all the info on the forums and went ahead with the NBS master cylinder upgrade. 10 bolt and9. Can anyone confirm my upgrade recipe for my 94 K Blazer 5. Is it worth needing new wheels and all the expenses to upgrade? *No need for this*. The door hinges on gmt400 suck Rear axel payload upgrade solutions 95 c3500HD? mooreATL; Aug 4, 2023; Axles New brake booster, new gmt800 cylinder, new calipers, everything Its been proven here that if you just do the GMT800 master with GMT400 other components it'll be worse I really wish the Forum owner/moderators would revise the various posts that suggest that as an "upgrade". As a side note: your brakes are a lot more effective if you don't jack the rigs up and put on giant wheels/tires. 1999 k2500 crew cab 7. This also applies to 4wd's as well. Pull both rods from both units and swap the '400 rod into the '800 HB unit. This is what I did to make my 98 The nbs master cylinder is meant for rear disc. The rod can be removed via tool made to press against the crimped metal housing where the ball is snug in. The rear brake upgrade made MORE difference than the front. I want to measure a 800 vacuum master to see if it would fit in the 400 hydrobooster. I never got fluid to bleed out of the lil' push-button under the rubber cover. Most of the parts are specific to that chassis, even its 6 lug wheels are oddball-sized. The OBS trucks are known for a horrible squishy brake pedal. The stud on the GMT400 Hydroboost pedal has a stud with a shoulder at the base and is larger than the stud on the GMT400 Vacuum booster. I've built a 6-bolt 14BSF rear axle for my C1500 and I would like to upgrade the front to the largest brakes I can fit into a 17" wheel, and obviously it needs to be 6-lug, too. 94 diameter piston. Just want to upgrade the brake system, to what will work properly. 05 is also when they went back to rear drums so if you are robbing the front brakes from a 99-04 you could snag the backs also for a 4 wheel disc setup Update: So I went ahead with the JB7 brake upgrade on my truck and its well worth the money. 15 vs. Originally I paired this upgrade with a master cylinder from a '79 Camaro with manual brakes. Electric brakes. Maybe if I wanted to deal with bleeding the brakes again I'll The above (plus GMT800 master cylinder) will get you Astro/GMT800 brakes on a 2WD. I up graded the front caliper's to 3. 5" tone 11" brakes for now. You need to find a C2500 with the same gear ratio as your truck (GU6, 3. 50R18s(at the smallest) on my 88 and I dont trust the stock brakes with my 31s. But I am also a little sour on my GMT400 right nowit's parked with brake problems. The economics of an upgrade are really reasonable: I bought the '96 for $3500 about 10 years ago. you can even throw a locker in the front diff of the 3/4 or 1 tons. There are two brake Next is a kit to convert to NBS/Astro knuckle brake upgrade. That "dead spot" that I know these trucks are famous for is gone. The difference between the setup's are, vacuum assist brakes use engine vacuum in a stored chamber to assist the vehicle in stopping, hydroboost uses hydraulic pressure from the power steering pump to the the hydro boost booster to assist in Front big brake upgrade, again Thread starter I know the GMT900 14 bolt from the 4x4 is near identical width to the GMT800 and we are swapping a 4x4 GMT900 14 bolt in my Getting the front wide enough just using gmt400 arms could be an issue not a problem I guess if building your own control arms though. He said his scan tool cost about 4k used. AFAIK the GMT400 calipers having the larger bores (3. Not sure on that one. Now on to the front brakes. The GMT800 master cylinder is a huge downgrade on any 1500 with stock-style the crappiest power-assisted brakes ever installed on a GMT400. Getting rid of the horrible 254mm drum brakes is a great plan. The best upgrade is switching to hydroboost. Anything else and you will have to move spring perches, shock mounts, and find adaptions/conversions for the brakes and U joint/yoke. When gm upgraded the brakes on the astro van they made a knuckle with gmt800+ style brakes that bolts in place of a gmt400 style knuckle I know this is a really old thread but what year did they upgrade the brakes on the astro? Jan 23, 2018 #3 S. The only difference For brakes both my trucks (99 C1500 Suburban and 98 K1500 RCLB) have hydroboost / 3/4 ton front calipers with good pads and the 11" rear drums. Has anyone upgraded to the 3. If not, maybe I'll just roll the dice, Amazon will return anything. Then As for an answer to what works for the GMT400 platform. NBS/Astro knuckle brake upgrade. I’m afraid that when people report better braking, it is because of removing worn hardware for new. I don't know what if anything is different at the rear. Drum brakes work great (especially those BIG ol' drums on a full floater 10. Even better, the terrible 254mm (10") rear brakes can be upgraded to JB6 spec, using 11. That said, the H2 was based on the '02 -'07 GMT800 2500HD chassis. Latest: ORVietVet; Monday at 1:48 PM; Introduction. If you search the part numbers, you can get the calipers for 400 each and 70 bucks each for the rotors. 5" rear shoes but the same drum. 5 14 shared the same 4 bolt flange. on the two wheel drive GMT400's they have a rotor with a packable bearing. Recently discovered my master cylinder in leaking in the front. Between quick take-up systems, drum versus disc proportioning valves, and the liability of grinding on brake components to get them to fit, there's way too many opportunities on our trucks to end up with a brake system that feels How to swap out the squishy brake pedal for a firm brake pedal. people are using metric s10 calipres or eldorado was the first swap. Once you bolt it in via the studs, the geometry is spot on with the factory GMT400 brake pedal. Me? I upgraded my K1500 pickup to the brake system your 'Burban has now. like i say happy to spend the coin on something custom so if anyone has any ideas let me know please! thanks ryan. I might need to go put the bracket and rotor off my dads truck now. x Duo-Servo rear Hello guys, is there a factory, bolt on, front brake upgrade available that will allow staying with 15" wheels? Maybe calipers/rotors from a newer year model or a 2500/3500 series? Looking to upgrade but don't want to have to buy new tires and wheels to do it. New posts Search forums. Best thing I've done the Those rear brakes, while I have nothing Especially since it may help enough to not have to upgrade the fronts when I get up to that half of the truck. Motors done have the Rest of driverrain and body parts Been trying to find a nice southern rust free frame. After reading the forums about changing this that and other thing someone mentioned to do an abs brake bleed. Credit goes to Rocky Thornton: If you do this brake swap on your OBS truck you will be amazed at the difference. The GMT900 brake upgrade not only came on some GMT800 Silverado and Sierras, (If they got good brakes in the front, they had drums in the rear. I picked up a GMT800 hydro master cylinder for it because of threads like this and it wouldn't fit the 400 booster. That being said if have rear drums they require a constant 10psi the obs master cylinder has a provision for this. The hubs were different but the OBS axles fit the NBS hubs perfectly. AZ Pro Performance Front and Rear Disc Brakes for GMT400 Trucks. Next, you need to upgrade the front rotors and calipers. The GMPP brakes that utilize a 16" Brembo rotor and 6 piston caliper would be nice to see on a GMT400. Is this a direct bolt on caliper. Yes it will work but you will no longer have rear brakes. The push rod distance was different between the GMT400 and GMT800 also. The brakes on these trucks suck. Richard In this video, I will show you how to do a Brake Master Cylinder Upgrade GMT 400 '88-'98 Trucks. I upgraded to a GMT800 Master Cylinder a couple of years ago and didn't see much difference. Now, you can find the older style 14 bolt FF under the CUCV trucks. 0, and 4:10 gears. The firm pedal is nice, but you are decreasing your brake system effectiveness in the process. Soft brakes (no lights on, nbs upgrade) obssuburban; Jun 12, 2024; Axles + I wouldn't recommend just swapping a GMT800 booster in place, unless you swap the entire brake system, including a GMT800 hydroboost. better brakes, front and rear end, bolt in a 4L80e trans (better than the 4l60e). DRW 3. GMT-400 to GMT-800 brake conversion tie rod discussion | The Truck Stop . This idea came from my research which showed that the new trucks use a huge rotor but share the 6x5. I don't know what the GMT800 has for a brake booster, calipers, pads or rotor diameters. Them being single piston calipers, does not really make them inferor to the gmt800 rears, but might come into play when finding a NBS/Astro knuckle brake upgrade. 6 KB as are the GMT400 JB7/JB8 MCs. I don’t understand how vacuum boosted gmt900 brakes can feel so much different than gmt400 brakes. Thread starter 99GMT425; Start date Sep 15, 2013; Disclaimer: Links on this page NBS/Astro knuckle brake upgrade. Basically, if you go GMT800, you should go all the way with a For the front? I hear tell that the 2500 calipers will bolt right in place of the 1500 ones, but I haven't actually done it yet so no guarantee. So in addition to reaming upper balljoint hole, I reamed the GMT800's tie rod hole to fit the ES409R tie rod. The JB7/JB8 calipers are a non-low-drag design, appropriate for the non-quick-take New to GMT800. Bought to tow a small travel trailer (4500lbs loaded) dual axle. $80 as pictured. Anybody know of kits that give it a little more stopping power that aren't crazy expensive? glad this thread came up. look at a gmt400 heavy half or 3/4 or 1 ton frame/axle. I had to drill out the ring I welded on. A GMT400 end will not bolt into a GMT800 knuckle. Thank you for pointing that out, I was not aware. 25" or a NBS 2001 1. Even those 18s Upgrading the rear brakes was at least as much of an improvement as upgrading the front brakes AND upgrading the master/booster. 3. As I've said on other posts, it takes a REAL disc system to equal the braking power of the 11. The fact that Little Shop of Horrors offers to "upgrade" brakes by deleting Federally-mandated safety equipment is a concern of mine. 7, 700r4. My goal with this project was to upgrade the brakes on a 1999 k1500 suburban to roughly 70-80% of the GMT800 (NBS) duramax. It was easy to make the brake pedal rods mate up, Are the hydro lines and fittings the same between GMT400 and GMT800 hydroboost? Can anyone confirm if I should use the AC Delco 19295627 Master Cylinder from a 2005 with rear drums to do this upgrade? Jul 17, 2019 #126 L. I have come There are two brake packages for the 2500 (3/4 ton), one uses 2. Perhaps I read about the gmt800 master, bought one for a 2001 c1500 with the front port adaptor, installed, float rear axle upgrade and will give me 13" brakes in the rear but still using 8. Check out www. The purpose of this upgrade is to improve the feel of the br There is a shiny new master cylinder from a 2005 Silverado hooked up to my booster. 285" diamter piston. Thread starter vogey; Start how you can basically bolt on gmt800 2500hd/3500 knuckles/spindles lower/upper control arms calipers and rotors on our gmt400 2500s. com) AND swap to a GMT800 MC and braided hoses on front and rear. 5" full floater and the 8. "My vehicle is a 97 K1500. Many people swap the master cylinder from a GMT800, is that what you're thinking of? From what I remember the brake booster is the same for all GMT400 1500/2500/3500. 4L 4L80E. Richard Interior, I prefer the GMT400 looks, but my GMT800 Vortec Max is very comfortable to travel in, but cheap looking. These are the upgrade brakes you'll see on some of the big late model SUV's My old K1500 had a gmt800 Tahoe MC, gmt800 single piston rear disks and 8 lug front calipers and that was by far the best K1500 brakes I’ve ever driven My K3500 is getting the Lugnut4x4 rear disk conversion with JB7 calipers so I’m curious to hear feedback on the negatives of that setup The larger piston on QTU-equipped masters sends this fluid in a much shorter pedal stroke, so the GMT400 brake pedal initial "mush" is the QTU feature in action, sending fluid to the low-drag calipers. Sorry guys with 6 lug trucks and the 10 bolt axle, I'm unaware of any brake upgrades for them. If I ever find the "right" gmt800 with the 8. That upgrade also must use the thicker dually rotor. The braking feels different, but I also swapped in a 14 bolt semi floating rear axle with bigger drums at the same time. My front brakes were SHOT and yesterday I replaced the rotors and pads with a set from Powerstop (K1990-36). Sewlow answered Don't ask questions if your gonna be a keyboard warrior against people trying to help. The factory gear ratios for teh rear are the same as the fronts. Thanks . 7 vortec. They did have non HD 8 lug 2500's, they came with the 14b semi float, the 2500 suburbans and trucks with the 6. Hi, A couple years ago I changed the rear cables and the equalizer/adjuster on my parking brake (The adjuster snapped). Reactions: HotWheelsBurban. 92. I was going to just do the GMT800 upgrade, but it's much easier to get the rear drum master cylinder for the gmt900. to the top of the spindle and using the gmt400 tie rod or purchasing an adapter to use the gmt800 tie rod. My mechanic wasn't sure if the tool had that option for my 98. Even the NBS brake hoses fit the OBS brake lines perfect. Axles + Brakes; 2 3. Sensors are in the hubs and they do work with the gmt400 4wabs system. x Duo-Servo units instead of that craptastic 254mm Leading-Trailing shoe system. GM offerred these from the factory on TAHOES sold for police and fire department Hi there , I just picked up a 1993 k1500 blazer 4x4 with 6 lug wheels and want to upgrade the front brakes as my wheels are 22 inches and stopping power needs improvement The GMT800 brake upgrade is NOT an easy swap on a 2 wheel drive, it's not even really possible to swap 800 spindles onto a 2 wheel drive 400 without extensive modifications In my experience, I found that the 1500 (5 lug) and the 2500LD (6 lug) are identical far as the pads, calipers and size of the rotor. You'll need four U-bolts and nuts, a conversion U-joint, (Precision 447 or equivalent) a rear-cover gasket, gear lube, and whatever repairs the brakes need. With that said you are very wrong that brake system is and was inferior. hi all i know there is a brake upgrade for the 5 lug obs trucks but is there anyone that does it for 6 lug? i have tried ssbc but no luck!!! anyone know of any others, quite happy to get it custom made also!! would need to suit standard obs spindles but. either the 1T 1. Brake drag has to be minimized to meet CAFE requirements, and to be competitive with "official" EPA fuel-economy estimates. They are alot stiffer, stronger better brakes ect. Located in brazos Forums. 1, my gmt400 will become our plow truck. Thread starter 99GMT425; There are some pretty good options for GMT800 and GMT900 trucks that would be awesome on a GMT400. I got a set of knuckles and lower control arms from a 1999 Silverado 2500 and a complete rear axle from a 2002 Silverado 2500HD. 15 aka 80mm and 3. So i've got this 1/0 wire, 1/0 - 3/8 copper lugs, heatshrink, a 300 ANL fuse, wire cutter, and hammer crimper. The wife unit drives a 1999 K2500 Suburban with the 7. Remember, that video CANNOT work for '88--'99 because GM used FOUR DIFFERENT ABS units in the C/K pickups in that time frame--Cast-iron RWAL, aluminum RWAL, EBC4, and finally EBC310 starting on the C/K in '95. 6 lug trucks used a 2. I was able to get my truck over to the shop today and he did the abs brake bleed. the LS trucks are much more efficient and modern and respond better to upgrades. So far, what I have come up with, is that the GMT800 spindle is shorter than the spindle you are using. Forums. For me, if there’s no brake improvement aside from ease of maintenance, I’ll just keep my 10” drum brakes. Thread starter 99GMT425; Start date Sep 15, 2013; Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. I have no idea if the GMT400 master works with the GMT800 HB Assuming from your 1" rotors you have the standard duty brake package. I'm perfectly happy with it. Can be installed with some modifications in a gmt400. 94" diameter piston in the front calipers, 8 lug single rear wheeled trucks used a 3. Thanks in advance. (7200lbs). Joined Apr 11, 2013 Messages 506 Reaction score 213 Location Western WA from Eastern WA, aka the wet side from Except that on a 1500 GMT400, you almost certainly have low-drag calipers, and the GMT800 master cylinder does not have the third, gigantic piston at the back that the low-drag calipers require. Super easy to do as well. that would be my recomendation. I fixed it by adding a hose clamp there. I think the only part that "might" be used off one, is the rarer Trailblazer SS 14 bolt SF axle, and Im positive the width, and mountings are completely off from a GMT400 chassis. You need spindles, rotors, bearings from a C1500 with "HD" brakes, or from a C2500 light duty (same truck you spec'd the rotors from. 1 and diesels had the 11. Joined Aug 20, 2015 Messages GMT400 Contact us; Perform a master cylinder upgrade to the gmt800 to start then you can swap to the front knuckle/ brake swap and rear brake swap to The front knuckles are close but the ball joint holes need reamed out to the correct taper to match the gmt400 ball joints. ) The standard duty brakes from the early years have spindles that are too short to use those rotors you bought. Consider upgrading the rear brakes, too. 38 piston, plan to run the DRW 370 pads (will grind backing plate as needed as noted on page1), rear wheel cylinders to the 1. Joined Nov 6, 2010 Messages 2,531 Reaction score 122 Gmt400 brakes-master cylinder upgrade, residual valves, disc/drum MC I know, is quite the stretch. Also, there were two different versions of this brake upgrade. I’ve got a k1500 with very squishy brakes. I think I need a better brake controller as well. Jul 24, 2024. I purchased the "PowerStop Z36 Truck & Tow" Front/Rear kit and installed them on my 04' Suburban Z71 4x4 5. 15" and pads from a K2500 8 lug (8600lbs) Had to grind the front outer pads just like Nitro Junkie posted on one of the pervious pages. It's 10mm actually. 0 had a 10. I have a 96 GMC Yukon 2 door. There was no mention in any thread I read about changing the booster during the upgrade. You'd be lucky, avoiding the horrible 254mm So I have a 98 k1500 with a 6 lug 14 bolt rear end and JB6 brakes. The front brake upgrade was noticeable. Your 254mm rear brakes are just about guaranteed to be WAY out of adjustment. The brakes still need to stop the vehicle without excess pedal travel. Were I to repeat the brake upgrade process on another GMT400, I'd just start with the HB and likely be done at that point. littleshopmfg. The rear brakes are a friggin' disaster. On most of these trucks the back brakes dont work unless you adjust them. Just checking to see if someone has done it before. I'm looking at switching to the JB7 calipers (pn: 18-4123) and the JB7 master cylinder. I'm not quite sure what happened there. 6" rotor. The Pedal came from a 96 C3500. The problem in doing the gmt800 and 900 swap is the lower control arms and balljoints. Not bad for 15" rotors and 6 1994 Silverado C2500 Master Cylinder Upgrade to Dorman M630031, Brake Line Adapter: BLF 26 (1/2M – 9/16F). Joined Nov 16, 2021 Messages 197 Reaction score 362 Location Ohio. GMT400 Contact us; I've seen where people will use the lift knuckles for a gmt800 2500hd with the gmt400 k1500 lift kit that way its easier to convert to 8lug up front and then you have 2500hd brakes instead of gmt800 1500 brakes, doubt its just a bolt up swap but I've seen a few of them so it shouldn't be to bad other than the cost of all that. The only one I could get was by Dorman and as soon as I went to apply it with any bit of tension the one cable pulled through. I believe the PPV tahoe brakes are the same as that performance brake system but with uncoated calipers. Any suggestions would be appreciated. 15 calipers from the 8 lug (8600lbs) calipers. So am I correct in that a proportioning valve? along with an upgraded master cylinder is the best initial route to get the truck on The GMT800-style master cylinder cannot work properly with low-drag Hi I am new to the forum. brakes/master/booster can make a significant difference in braking power. For the rear, only the 14bsf of of another OBS is a direct swap. I have front calipers with the 2. im pretty sure that i have a sticking caliper and was thinking about upgrading them since i do have the 3/4 rear endthose brakes work alot faster than the front ones do from higher speedsthe rear will lock up long before the front even thinks about im gonna have to get me some 2500 front calipers now The taper didn't fit the GMT800 knuckle as is. It's definitely worth the upgrade. Thanks Craig In this video I walk you through upgrading a GMT400, or 88'-98" Chevy/GMC brake master cylinder. Tried searching and im wondering if anyone hase ever pulled off a new body style gmt800 2500hd frame swap in one of these trucks. "Heavy Duty" brakes on a 1500 would be JB6. Magnefine F I tried like in the video, and got nowhere. Looks like a big improvement over the stock setup. I also installed all new brake lines in the front and rear, also replaced both rear wheel cylinders, brake rotors, pads, wheel bearings, rear brake shoes. 5 full float all factory disk brake with internal parking brake from what I have seen. I upgraded the rear axle and rear brakes a couple of years before upgrading the front brakes, master, and booster. Brake booster upgrade? It's time to replace the booster in my '88 k1500 5. I had to buy parts anyways so I went with a set of 2010+ GMT900 Calipers, pads, rotors and brake hoses to upgrade to the 13" rotors instead of 12". I'm in the process of finishing the the 800 dual piston brake upgrade. I purchased Dorman M630031. . Looking for pros and cons on choice of 1T front calipers SRW 3. I think this is a bolt-on for 2WD--just buy the I'm going to upgrade my master cylinder and brake booster since they're both questionable. x Duo-Servo rear drums and mechanism. Reactions: jrsavoie, MrMarty51, FellowTraveler and 1 other person. The rear brakes need a 20mm spacer for the backing plate/mount to the axle Brake upgrades using factory parts for GMT-400(88-00 OBS), and 94-99 DODGE 2500/3500. the srw 1 ton piston is 3. I honestly didn't realize it was that difficult. If and when I do an upgrade it would be the 9. Axles + Brakes . The tierod stud hole was the same on both, just had to turn the tierod 180-degrees. I had an Allstar Performance 9. Cheap GMT400 brake upgrade (mostly for Suburbans) ShawnG PowerDork 6/15/19 6:11 p. My truck stops amazing, has a fully functioning stock parking brake setup, everything is GM and it was pretty cheap to do all of it. Is there any merit to anything I just wrote? The Powerstop upgrade is I think a good upgrade. 50 caliper with the smaller 11. The most popular GMT400 brake upgrades include: GMT400 rear disc brake Has anyone tried the brake upgrade using the 2019 and up rotors and four piston calipers? Found this video on it. If his feet get too much traction he hops up and down to keep me from spinning out. Dec 2, 2015 #12 and even better as a compliment to any upgraded brake kit. 5" range where the GMT800 is around 65" so the rack shouldnt be too wide. I was reading about brake upgrades online. 130" or 13" rear drums. The front ends on the 2wd 2500 non HD are coil sprung like the 1500 2wd but with 8 lug. a bigger master should be used, disk brake calipers use a higher volume of fluid than a set of wheel cylinders, usually a stock master will work but the petal throw will be much further and you will tend to over work the front brakes, that is why most offroaders who go rear disk also swap to a early 90's 4 wheel disk c3500hd master that was designed with a bigger Is there such a thing as a big brake upgrade kit for the front and a disc swap in the rear? Primary concern is highway use at speed. You'll need the Ford/3 prong attachment part # 1107 for the 2002 Silverado master The GMT800 master cylinder firms up the pedal because it has more piston area than a GMT400 master cylinder. The most expensive part was the rear axle spacers to adapt the GMT800 disc brake backing plates. Beyond that I’m not sure, but I think it is possible to put GMT800 spindles on which gets you only slightly bigger rotors. 4 disc brakes are nice. If you have a mish-mash, go fully GMT400 or GMT800. Brakes are fantastic! A Motive Power bleeder works well for getting all the air out. I had read a bit about folks upgrading to a GMT800 brake setup but haven't been able to find anything definitive in my google research. All connections are tight and all 4 corners bled. My 2003 2500HD crewcab Duramax weighs in at ~4 tons and thanks to hydroboost (and much better rotors and calipers) , it will stop on a dime. But YOU better know. 33". The nbs mc does not. I installed a GMT400 ring on the GMT800 booster. New posts Search brakes and interior goes. I can see the want for good looking parts on your truck though. The GMT400 brake line fitting is metric. Been eying these a Doing a modified restoration on a 94 k3500 srw rclb. As soon as he sees the third brake light he jumps out of the back, holds on to the tailgate and slows me down Fred Flintstone style. jpg. The only difference being the size of the piston. Found a pretty significant leak on the hydroboost unit in my '99 3/4 ton Suburban yesterday. 2. Front big brake upgrade, again Thread starter realsquash; My nosing around reveals that the track width for a GMT400 is in the 63. Picture 1. -NBS 1500 series master cylinder (buy the corresponding master cylinder for your truck, 1/2 ton=1/2ton, 3/4ton= 3/4ton)-AGS BLF 26C brake line adapter (I got mine at autozone)-DOT 3 brake fluid I decided to try the brake upgrade that Lawrence Tolman was showing on his Youtube channel. The ABS wires plugged right in,too. I did the GMT800 front, Russell braided lines all around, GMT800 master up front (make sure it is the 34mm bore from a ~2002 Silverado). Unless The Powerstop upgrade is I think a good upgrade. Have a complete hydroboost with master and pedal from gmt800. Oddly, on RockAuto, I find disparities in the specs. bought with upgraded brakes, 4 wheel disc , from a gmt800. I was looking through the front brake upgrade post and it seams like would go hand and hand with the master cylinder upgrade. It fits tight. Be prepared to find all sorts of other issues as you take the suspension apart--PS pump, PS gear, rusted frame at the PS gear, brakes including metal tubes and rubber hoses, ABS, disgustingly contaminated brake fluid that needs to be flushed using a scan tool to chatter the ABS solenoid valves, ancient front or rear differential lube, leaking differential seals, etc. The cherry on top is the hydroboost with HD master cylinder, truck will lock the 33s down hard since merely adding HB. 7. For those with 6 lug wheels, you DO I'm hopeful that with a few upgrades like regearing, a bit of brake work (NBS knuckles, new MC, new brake lines, and rear disc) throwing on helper air bags, Gmt800 master on gmt400 hydrobooster. If you have GMT800 brakes, you want the GMT800 master cylinder. I have a 88 GMC K2500 with 6 lug wheels. It is an adequate replacement for the 5. 38 aka 86mm, typically deployed on 2500/3500s with JB7/JB8 brakes), are not the "low-drag" type so the NBS MC will work well with them (as will an MC designated for JB7/JB8, as it They have in my opinion the best type of Parking brake set up, (Drum inside the disc, GMT800 rear discs are the same). I do tow multiple times a month, run larger tires and on one of my longer trips where I was towing, had some issues with overheating. I didn't modify the proportioning valve as the instructions said that they "advise" you to and didn't state that it is "required". So, you have a GMT 400 truck, but the brakes are somewhat crummy You have some options. I would love to make my brakes work a bit better on my Suburban with the GMT800 Master as well which I believe requires the GMT800 hydroboost. I recently trailered a Trailblazer SS on a open trailer and it was kind of sketchy. I cover the most common GMT400 brake upgrades. There are many GMT400 upgrades centered around the brakes. Attachments. My 1500 came stock with the 14 bolt semi-float rear axle (6 lug) so I swapped in the bigger wheel cylinders, JB7 master cylinder and braided hose lines all around. 5x5), but that can be redrilled. I think you said somewhere i need to pull the front brake lines and valve out of a 88-94 and the bend the rear line I also just upgraded my 97 GT Gmt400 to Hydro also -if you haven't done the NBS master cylinder swap, now is a FANTASTIC time to do so. The T1XX factory option "big" brakes w/13. I went to the NAPA parts store for fresh calipers and rotors and made another huge discovery. 7L (already swapped in a 14SF). Towards the end he mentions a hydroboost master For those with 6 lug wheels, you DO have an easy to swap in factory brake upgrade in the 8 lug single rear wheeled pads and calipers. you have a ton of options. HotWheelsBurban. 5") and you won't have the issues some of those disc rear GMT800 trucks had. your cross car depth is what youll Just did this too It’s an awesome upgrade. I'm looking at 1998 Chevy K3500 The vacuum booster is factory GMT400 and the cylinder is GMT800. Brakeshere is the one place the GMT400 CAN NOT (in stock form) touch the GMT800! GMT400 brakes (non hydroboost a little smaller. 5" bolt pattern and 78mm center bore diameter as the OBS K1500 rotors. Jun 4, 2020 #39 K. Stick with a GMT400 rear and drums. 42), grab the 9. Will the original brake hoses work. The pedal feels way better. yea. A properly-functioning JB6 is all you need. (pn: 131-66008) My original plan was to switch to rear disks but @Schurkey made some good points in a couple different threads about those Just watched a video on YouTube showing how you can basically bolt on gmt800 2500hd/3500 knuckles/spindles lower/upper control arms GMT800 brakes n susp parts on gmt400. Brake pedal is really soft after changing fluid and replacing front pads and rebuilding the rear drums. Let’s face it: These trucks have a perfect wheelbase, amazing body styling and, when they were new in the ’90s, a reliable and strong factory The newer disc brakes--that are used in the Street Truck article, conversion parts made by Freeman--trap the pads in a second, solid iron bracket with no rubber O-rings or screw-in pins, that was designed from the beginning--by COMPETENT engineers--to accept brake torque on the inboard side. 285" i don't think much gain if any came from the drw pads over srw but they are a bit thicker and designed different. Joined Aug 9, 2015 I've done some searching but most of what I see is for 1500 Vac to hydroboost. GMT400. laxman21 Newbie. So in my research on the NBS front brake upgrade for our trucks, For the 3/4 ton/1-ton trucks, the 99-00 non-HD NBS steering knuckle/spindle will accept the GMT400 tie rod end without modification, same as the threads on this brake swap. I am looking for a brake upgrade for towing. Click to expand 400 vacuum brakes suck and for the gmt800 master swap to work, we’d need a QTU master I have a 96 C3500 CC DRW, 7. While an improvement, is it a substantial improvement. Jan 29, 2024 #10 El Tigre I'm With the replacement parts situation I am thinking that a ABS delete leading to a full new brake system later on in the process. It took about 65-75% of the brake pedal travel to get the rear wheels to stop in 1st gear idling. I need to go through and clean this post up and add more to it that I have learned since I 1st made it. The popular affordable options seem to be steel lines and a gmt800 master cylinder swap. Donor truck was a 2003 2500hd. Supercharged111 Truly Awesome. m. The GMT800 had dual piston sliding calipers with about the same total area as our single piston calipers but it also has more boost built into the In a truck as old as the GMT400, the installed brakes can be mash-up of God-knows-what, One upside the NBS is its larger reservoir is suitable for rear disk brake "upgrades", Well, the time has arrived, Us 2wd Guys can have the same brake upgrade as the 4wd guys, anyone intersted I'll Post some pics and parts list once completed. I have a 1989 K3500 SRW. I have a 1988 GMC C1500 5. 5" rear axle assembly and U-bolt plates. you can swap dual piston 800 burb brakes, 900 brakes. They both stop great and use OEM parts. The REAR brakes are a bigger problem than the fronts on the JB3/JB5 vehicles. I was planning to keep the JB6 booster and front calipers and rotors When you find one, write down the year, model, and VIN number so you can order replacement parts to suit the brake system you take from it. Hi Everyone! This is my first post, but I have been wrenching on trucks since I was in my early teens. It seems easy enough to go hydroboost to hydroboost other than swapping the mounting plate from the GMT400 hydroboost over. Yes my 04 clears 16s no problem an has dual piston calipers front and rear, in 05 they went with bigger brakes up front that require 17s+ so if the donor truck is a 99-04 your good to go. realsquash Newbie. Reactions: MG95_c1500 and Dirty_Black_Z71. The Astro brake hose appears to have 7/16" X 24 thread so I used an adapter with 7/16" male to 3/8" female inverted flare and just replaced the nut on 'Burban brake line. Also FYI in the 2500's it was more typical to find a full float in the 96-up trucks; a lot of the earlier 2500's got semi float. With all new parts fairly recent, it functions as good as new with only a bit over 60k on truck. There is a ratio difference between the two. 3L. partsman57; Thread; I know it’s been gone over thousands of times, but I’m trying to get a clear picture of what I need to do the upgrade. Because it has factory this summer will installing 2000 suburban package on my 89 GMT400 4x4. More members show up. This mush is much longer with the GMT800 master, because of the smaller piston moving less fluid. I finished my brake upgrade on my 88 GMC K2500 6 lug (7200lbs). The usual trick that everyone GMT400 Brake Upgrade. 5" wide rear shoes and the other uses 3. Mostly, I need something that can tow better. Changing JN3 brakes to the equivalent of JN/JB5 front brakes/master/booster can make a significant difference in braking power. I just bought a 99 K1500 suburban JB6 brake package. I hired a gorilla to hang out in the back of my truck. I’m now looking into the master Vehicles with larger master cylinder bores tend to have more-powerful brake boosters to compensate for the lack of hydraulic advantage. I’ve done it on my Suburban as well, and was going to do the 2019+ Silverado brakes (much bigger) on my Avalanche, but the cost of almost $600 once you add up all the parts doesn't seem worthwhile, and these GMT900 brakes work so well. Solutions Hello I see a lot of people asking about Hydroboost swap's, so I thought I would do a little write up on one of these swap's. com. I’ve wondered whether the GMT800 DRW I did just had this done to my truck with a snap on. 4L . Most of what I found is half ton upgrades from vacuum boost Mainly the GMT800 MC firming up the pedal was the difference I felt. Otherwise, it has been a great truck. Compared to newer rigs the brakes on the 400s are small to start with, one of the biggest improvements on the newer rigs is larger diameter wheels, going from a 16" to ~18s or so let the factory use larger discs, big difference. I’ve read up on the GMT900 brake upgrade. romanos93; Feb 16, 2023; Axles + Brakes; 2 The GMT 400 brake system that you speak so highly of is one of our engineers most admitted failures, the DOT scored it with a "D" you must be the luckiest GMT400 owner in the history of GM. If the GMT400 and GMT800 1. 25” master cylinder are in fact identical, other than larger, different style reservoir, I have a 1999 K1500 with what I assume are JB6 brakes. I assumed the GMT400 MC didn't have a big enough piston to get enough brake pressure to the rear discs. If they had the disc brakes in the rear, they had the smaller brakes up front). I Looking to upgrade my brakes. There were some GMT800 2500s, they were sort of oddball trucks from what I've researched. 4l. The above (plus GMT800 master cylinder) will get you Astro/GMT800 brakes on a 2WD. theres a place called cunninham making a caliper bracket that uses stock k1500 front calipers. Everything I've read either talks about rotating the tie rod. how different are the GMT400 and GMT800 knuckles, i plan on running 35x12. Without 4 wheel discs, big rotors, and 2 piston calipers, I believe this is doable. 86 pads? Isn’t the pad to rotor surface the same? Is it just that much better a caliper? Not knocking any of this ^^^, just curious. Oh, and another thing; A Jeep SRT8 uses a 15 GM designed the 03 and up astro awd knuckle to bolt in place of the gmt400 knuckle on the astro and use the newer style Will updating the drums, on the rear to disk, allow the new nbs master cylinder, to work properly. I was think about seeing if the 05+ 1/2 front disks would swap over. Much better brake feel and a pretty good amount of additional braking I can't seem to find a thread with relatable information. The front brakes are tied together with a T, and the rear brakes have a wilwood adjustable proportioning valve. Joined Nov 5, 2010 Messages 11 It possibly could, but I have a GMT400 hydroboost sitting on the shelf to install in my truck. vthvi fhbd xnylozl ngwl zjuqqb amhl mgkhf rouqx atpjv kjlg