GMT 800 Brake Conversion > Silverado HD 2500

[Dustin Zynda]

Different people like different things- share what ya got and don’t worry about it. You do your truck your way.

I have done air ride work trucks before. I used to be part owner in a truck equipment shop. I believe you are really going to enjoy the ride. Flip of a switch lo compensate for the load and condition you want is nice. It will take a little playing with it to get used to finding sweet spot quickly. The difference of air ride can be impressive.

One example
On the bigger truck side-there is a global company called PRG, Production Resource Group, With locations in different cities like LA, Vegas, NY, etc. they sell& rent everything for movies, tv shows, live production stuff like lighting, sound equipment,rigging and have the workers that do it all. So many millions in electronic equipment that it is scary. They learned long ago all their equipment ONLY goes in semi trailers that have air ride. The equipment gets beat up in regular spring trailers a lot more. Obviously when a customer rents the stuff and hauls it themselves they can’t control it- but they tell them it’s better to make sure they don’t have a failure from it while touring.

Some people think metal spring has to be safer that rubber air bag... and yes the air bags wear out sooner. But if they were that unsafe there wouldn’t be all these semi trucks using them. I found the air bag systems on semis much less a headache to work on.
I'm working on installing a pretty much bolt on triangular 4 link with air lift bags over axle. I started this because I never really liked the ride and everytime my wife's with me holding her non travel coffee cup I am driving like the egg is under the gas pedal missing pot holes. lol
I also hate getting things off the roof rack, tool box and climbing into the bed. I'm a short legged and arm 5.9 tall guy, I use the tall part lightly. Steps help but not so much lifting a 32 or 36 foot ladder onto the roof.
I am not getting any younger and have past injuries that make it harder to function. I figured being able to ride nice, lower down for function and occasional shows.
My buddy and I argued about air vs hydraulic then I found hydroshox they are a coilover hydraulic with 4 or 5 inches of travel and sord makes large with more travel. These are all expensive options but cool options and I believe very daily functional.
These newer trucks are just getting bigger, taller. I'm not growing any so I thought I had to do something to make my life easier.

Hydroshox - Racing Products & Accessories

Metal Working Tools & Metal Fabrication Equipment by Mittler Bros

www.mittlerbros.com

SORD Shocks Hydraulic Coilovers

sord-shocks

sordshocks.com

 

[Dustin Zynda]

You need to chill. No one criticizing your approach here. In fact, all of us thanked you for posting the alternative. Some, myself included, defended against misinformation you posted about the other preceeding approaches.

These forums exist to provide information to help others. Your self acknowledged lack of basic machining skills should not dissuade others from attempting the other approach. There are +/- with each approach and that is all we were pointing out.

Yep your right I do apologize, certain comments can make a guy feel criticized.

 

[jrsavoie]

The difference is really what are the junkyards like in your area.
In vegas there was (idk if it is still this way) a truck junkyard where they fully disassemble the trucks, tag parts and shelf them. Getting the parts is like going to any other parts store- just call and ask for part “x” and if they have it they tell the price.
Then other normal junkyards where you wander around and diy it and parts are way cheap.
BigT $80 a pair is higher than here. Its been a year or so since taking a friend to get a set for his truck- My back was hurting so I just drove and relaxed in the rig next to it and just explaining what to pull apart because he never done it before. Came out fairly quickly and a set with knuckles for him was $60 total. No need to replace those bushings, they have many years left in them. No where near Cali prices.
But if the set Dustin shoed would have been a known option, he might have done that instead. So the quality of the rigs that go into your junkyard is a huge factor.
I just think it’s cool there is more options for people- everyone can decide whats their best one.

i wouldn’t think twice of needing to tack weld something because I have a welder, but many guys dont. Y’all boys that don’t need to watch a couple YouTube videos on how to use stick powered by your truck batteries. Really not bad for everyone to learn “just incase”


A lot of things some people see as consumable parts others don’t. I will never own a rig that would need a arms. All my rigs are always bought used-DESERT LIFE- so rust doesn’t exist.
But yesterday was helping a guy whose hummer needs a couple rears. 6 bolts removed from turbo heat sheild, none are worth installing back, 2 we were lucky got removed. A tbolt V band clamp broke and the other nearly broke. I am afraid his exhaust manifold sealing surface rusted and is causing a leak. Yet to my hummer none of that is even a worry -DESERT LIFE = no rust.

Different ways to skin a cat boys. I skin mine by ordering a hamburger instead and leaving the cats to someone hungrier than me.

So, you never eat Chinese food?

 

[Dustin Zynda]

Air lift makes them in different configurations they call them the builder series. You can get different bags and mounting styles. Just measure you min and max shock lengths, download there sheet and figure what works best for you. They have 3 inches of threaded travel and about 4 inches of air travel. That of coarse depends on weight, air pressure, pumps tanks etc. you can put to them. Airlift is very helpful and Iam communicating with them on my build because they are curious how it will turn out. I am not finished with mine yet, right now they are mounted and I have to jack it up to air it up. I have not hooked up everything yet, the lines pump and tanks. I'm using accuair which will go to 200psi.

Air Springs | Air Lift Performance

Universal air springs from Air Lift Performance provide the ultimate in air spring performance with more lift, higher pressure, and a softer ride.

www.airliftperformance.com

 

[Dustin Zynda]

Air Springs | Air Lift Performance

Universal air springs from Air Lift Performance provide the ultimate in air spring performance with more lift, higher pressure, and a softer ride.

www.airliftperformance.com

Thanks, I thought the link was included in my post. Sorry

 

[DieselAmateur]

I referenced welding in ball joints because that's the current reality I have on my truck. Passenger side LCA is so worn from ball joints being pressed in over 25+ years that they don't stay pressed in anymore and have to be welded.

Before I purchased the truck in 2016 it had a plow on it for some part of its life and that probably contributed to extra wear and more frequent ball joint replacement than normal.

In the 6 years I've owned the truck the lower ball joint has been replaced at least 2 or 3 times.

There's rough roads here in upstate/ western NY and I tow heavy somewhat regularly which probably accounts for more wear than folks whose truck is a daily driver.

Given how much of a pain in the ass I hear it is to remove the stamped LCAs, the last thing I would want to do is go through all that trouble, then install a 20 year old forged LCA, and in several years time encounter the same scenario of the LCA being worn out and not being able to take pressed in ball joints, putting me back to where I was trying to get away from.

So that's why I'll probably opt for the GMT800 LCA over swapping in forged ones. Less reaming to do is just icing on the cake

 

[Dustin Zynda]

I referenced welding in ball joints because that's the current reality I have on my truck. Passenger side LCA is so worn from ball joints being pressed in over 25+ years that they don't stay pressed in anymore and have to be welded.

Before I purchased the truck in 2016 it had a plow on it for some part of its life and that probably contributed to extra wear and more frequent ball joint replacement than normal.

In the 6 years I've owned the truck the lower ball joint has been replaced at least 2 or 3 times.

There's rough roads here in upstate/ western NY and I tow heavy somewhat regularly which probably accounts for more wear than folks whose truck is a daily driver.

Given how much of a pain in the ass I hear it is to remove the stamped LCAs, the last thing I would want to do is go through all that trouble, then install a 20 year old forged LCA, and in several years time encounter the same scenario of the LCA being worn out and not being able to take pressed in ball joints, putting me back to where I was trying to get away from.

So that's why I'll probably opt for the GMT800 LCA over swapping in forged ones. Less reaming to do is just icing on the cake

Just a heads up but I'm sure you know already. You may most likely have a problem getting the bars out of your old stamped arms and keys. The truck I just did is a 97 from Michigan and I pulled out the arms, bars and center support as one. I still haven't gotten it apart, I've just been spraying it and being patient. I have deleted the torsion bars though and opted for the new gmt800 lca because of ball joint where. If you can't get the bars separated it may be a better option to delete them rather then trying to replace them. I have 2 trucks with 300k on them and the bushings are worn out now. I drive hard, not towing or pulling like a race car so I want my trucks to perform well and safely.
With your plow weight and towing weight you may want to use the BDS bracket. I had a few guys look at the bracket and my setup and they all agreed it was overkill but that's not a bad thing. They interfere with the bump stop so I decided not to use them.

 

[Husker6.5]

So, you never eat Chinese food?

Sure, @Will L. takes the dog for a wok!

 

[DieselAmateur]

@Dustin Zynda What is the BDS bracket for?

I know I have lots of torch work/ heating & beating in my future when I try to remove the LCAs

I don't have a snowplow on the front, truck did in its past life but I don't subject my rig to that kind of abuse. I suffer in coveralls on a tractor without a cab plowing snow instead I would like to keep the torsion bars. I'm all about simple and an air ride system is too many moving parts for me in salt country

 

[Big T]

@Dustin Zynda What is the BDS bracket for?

I know I have lots of torch work/ heating & beating in my future when I try to remove the LCAs

I don't have a snowplow on the front, truck did in its past life but I don't subject my rig to that kind of abuse. I suffer in coveralls on a tractor without a cab plowing snow instead I would like to keep the torsion bars. I'm all about simple and an air ride system is too many moving parts for me in salt country

I was unable to get the torsion bars out of the stamped steel LCAs on my son’s 1994 K2500 Suburban. Took the whole assembly out when I redid bushings and ball joints. I have a set of forged LCAs that will be going on and intend to cut the stamped steel ones off the torsion bars using a grinder and cutting wheel.

 

[Dustin Zynda]

Just a heads up but I'm sure you know already. You may most likely have a problem getting the bars out of your old stamped arms and keys. The truck I just did is a 97 from Michigan and I pulled out the arms, bars and center support as one. I still haven't gotten it apart, I've just been spraying it and being patient. I have deleted the torsion bars though and opted for the new gmt800 lca because of ball joint where. If you can't get the bars separated it may be a better option to delete them rather then trying to replace them. I have 2 trucks with 300k on them and the bushings are worn out now. I drive hard, not towing or pulling like a race car so I want my trucks to perform well and safely.
With your plow weight and towing weight you may want to use the BDS bracket. I had a few guys look at the bracket and my setup and they all agreed it was overkill but that's not a bad thing. They interfere with the bump stop so I decided not to use them.

@Dustin Zynda What is the BDS bracket for?

I know I have lots of torch work/ heating & beating in my future when I try to remove the LCAs

I don't have a snowplow on the front, truck did in its past life but I don't subject my rig to that kind of abuse. I suffer in coveralls on a tractor without a cab plowing snow instead I would like to keep the torsion bars. I'm all about simple and an air ride system is too many moving parts for me in salt country

They are made for supporting the coilover in there gmt800 kit which is a 4.5 lift.
I bought just the brackets because they are beefy and thought I would need them. I did not want a lift but I thought with the weight of the big block and all it was the way to go. They seem to be more of a problem and some fab guys said that lower gmt shock mount was enough so I guess I will find out. Coilovers or air shocks would be easy without a lot of moving parts but your probably in the 1k for pair price. I honestly think a coilover would bolt right in without modifications to the upper mount. The bags are close they needed a few inches extensions.
You won't need all that if you're keeping your bars then.

 

[spdgofast]

Hey guys, I was just starting to work on my front brake conversion but I'm not quite ready to swap the rear axle to a disc brake 14 bolt unit. My problem is my hydro boost just started leaking so it needs to be replaced. My question is I know when swapping to rear disc brakes I need to swap in a 3500 HD master cylinder but do I also need to install an HD hydro boost or can I use the original 1994 K2500 hydro boost unit? I'm hoping the original version will work down the road when I do the rear disc install or will I be buying 2 different hydro boost units since I'm not ready to do the rear yet?

 

[DieselAmateur]

I didn't know it was required/ there was consensus that rear disc brakes require the 3500 HD master cylinder. Rear disc brake kits that convert drum 14 bolts don't say anything about needing to change the master cylinder, but I acknowledge there may be a difference in swapping to the 11.5 AAM 14 bolt, if that's what you're swapping to.

Folks on here convert to the GMT800 front brakes without changing the master cylinder or hydroboost, and the front brakes do about 70% of the total braking, so I'm wondering if changing anything there is necessary for your application. Not saying you're incorrect, please do share what you've researched/ learned as it's important information we can all benefit from. Hopefully someone else chimes in with more knowledge than I.

 

[Big T]

Hey guys, I was just starting to work on my front brake conversion but I'm not quite ready to swap the rear axle to a disc brake 14 bolt unit. My problem is my hydro boost just started leaking so it needs to be replaced. My question is I know when swapping to rear disc brakes I need to swap in a 3500 HD master cylinder but do I also need to install an HD hydro boost or can I use the original 1994 K2500 hydro boost unit? I'm hoping the original version will work down the road when I do the rear disc install or will I be buying 2 different hydro boost units since I'm not ready to do the rear yet?

I’m close (maybe this upcoming weekend) to installing a GMT-800 14 bolt full floater with disc brakes on a ‘94 K2500 Suburban and have no plans to change the hydro boost. Never heard of this before.

 

[Twisted Steel Performance]

I did a disc conversion on my k3500, nothing else was changed, the manufacturer of the kit says nothing is needed. My brakes work much better than stock ever did.

 

[MrMarty51]

I need to do something about the brakes on My K3500 SRW.
Stepping on that pedal reminds me of that old tune, Wolf Creek Pass by CW McCall.
Sorta like stepping onna plumb.

 

[Twisted Steel Performance]

This is the kit I used...

This area is password protected [401]

 

[Big T]

This is the kit I used...

This area is password protected [401]

Back in the day I looked at the GMT-400 disc brake conversion kits and they were priced at $580. I see they are now over $1200. My entire axle cost me $260 harvested from a Pick-A-Part boneyard and that was complete with rotors, calibers and pads. The spring and snubber perches, plus the welding added $100. Just ordered a parking brake cable equalizer for $15 including taxes and shipping. Way cheaper than any conversion kit I priced.

 

[spdgofast]

From what I recall when going to 4 wheel disc you had to switch to a 4 wheel disc brake master cylinder and proportional valve which I believe the easiest swap is the 3500 HD master cylinder and the HD proportional valve. I was not sure of the hydro boost, I will be installing a 2001 14 bolt with discs when I do the rear so I guess I can just replace my hydro boost with the one that is called for a K2500 Suburban and it will be ok when I install the 01 14 bolt disc axle. Next question is the OEM hydro boost is discontinued, so what is the best replacement? All I find available is a Cardone unit. Which one has everyone been successful with?

 

[Big T]

From what I recall when going to 4 wheel disc you had to switch to a 4 wheel disc brake master cylinder and proportional valve which I believe the easiest swap is the 3500 HD master cylinder and the HD proportional valve. I was not sure of the hydro boost, I will be installing a 2001 14 bolt with discs when I do the rear so I guess I can just replace my hydro boost with the one that is called for a K2500 Suburban and it will be ok when I install the 01 14 bolt disc axle. Next question is the OEM hydro boost is discontinued, so what is the best replacement? All I find available is a Cardone unit. Which one has everyone been successful with?

No on both, thought there was a proportioning valve Service Bulletin to upgrade the rear braking power for the GMT-400 Suburban. I’ve done that mod on my ‘99 but not on the ‘94.

My post on this from another thread:

I converted to the GMT 800 front disc brakes, but that was on two K2500 Suburbans ('99 and '94). I retained the stock mastercylinder and hydroboost, though some here speculated that doing so would ruin pedal height. I actually saw improved pedal height and firmness. I still have the stock drum brakes on the 14 bolt full floater rear end, though I have a GMT 800 14 bolt full float with disc brakes prepped and ready for install on the '94. I did install TSB recommended proportioning valve which boosts rear brake pressure from 600 to 800 psi. My ABS has never worked and I have been unable to figure that out, though it might be due to transfer case. In panic stops, all wheels lock and no I don't have the rear end becoming the front end. The braking power is impressive.