Brake Problems - GM 3500HD

[Hatchee]

THANKS!!! I will raise this with the dealer.

[kdauto]

Originally Posted by Hatchee

2016 GM 3500HD has violent front end shaking when braking.

6/8/17 - 22,890 Turned Rotors
9/25/17 - 29,752 New Rotors
12/11/17 - 36,282 Dealer says nothing wrong
1/11/18 - 36,833 Calipers sticking, bolt rubbing - replace rotors, shoes, calipers
7/19/18 - 48,764 Replaced rotors
8/2/18 - 49,540 Modulator valve found to be bad, replaced rotors & pads
9/13/19 - 74,560 more violent shaking. Have not taken to dealer.

Too date, the dealer has done all work under warranty but I have lost total faith in them actually determining what is going on. All new pads and rotors match original equipment. Locally, there is a very good independent mechanic who has done all work on our vehicles after they are out of warranty for the past 20 years. Considering taking it to him but concerned that GM will not make it right if he finds something is defective.

We are schedule to leave for New Mexico to pickup 34' 5th wheel on 10-5.

Opinions/suggestions?

I have experienced the same at one point on my 2011 GMC dually. I doubt the brakes are much different. I had never had an issue until some very tough mountain towing at well over 120 000km. I machined the rotors only, iddn't last more than a few thousand km when used hard.

I have seen this same issue a few times on different vehicles, usually using OE (original equipment) pads. My findings seem to be too "soft" a pad. GM uses Akebono on most of their trucks, was on mine. While they are a great and very durable pad, they seem to deposit too much material when run very hot. This leaves a smear of pad material on a spot of the rotor whick keeps accumulating material vs the rest of the rotor suface. The technical term is RTV (rotor thickness variation). A competent technician can measure this with a dial gauge setup.

I have tried replacing rotors only and have the issue return rather soon. Best to replace pads and rotors. On my truck I tried Powerstop pads and cross-drilled and slotted rotors. They are really inexpensive and work. I've now gone 15 000 to 20 000km with no pulsation.

If your rotor was really warped the brake pedal would be pushing and pulsating against your foot as well as the steering vibrating. With RTV, only the steering wheel shakes.

I am starting to feel the same issue with the rear of the truck now at 170 000km. Too bad because I replaced the fronts with 10 mm of pad remaining and I have as much left on the rears currently. I'll probably do the same out back real soon.

[redhooker]

Something is causing this. I have 96k on 2015 3500HD DRW original rotors zero vibration. Had to replace my rears for cracking issue but they also did not vibrate. I tow heavy and live in Florida so they see some heat. BTW this Also is not my first HD and all prior trucks had similar brake life.

Something is causing this issue there is no way oem rotors should warp that fast. You need a knowledgeable mechanic to diagnose the root cause. The only thing I know would cause it is dragging the brakes but I will give you the benefit of the doubt and assume you do not drive with both feet.

[V3600]

I also have a 3500 dually. I used to think it was my rotors but no more. The shuddering comes from uneven brake pad deposits on the rotors.

Last time I did my brakes I roughed up the rotors with wet sand paper to remove the brake deposits. I could have had them turned but I was curious how this would work. The old pads were put back on as they still had plenty of meat left on them.
Afterwards I took the truck out to burn in the pads. Old fashioned but it works.

I accelerate my truck to 45 mph then slow quickly to 10 mph and release the pedal pressure. Let the brakes cool for 30 seconds then repeat 3 or 4 more times. No more brake shuddering. No more need to turn rotors or buy new ones.

Also, the lube I use is Permatex Ceramic Extreme in the lavender colored bottle. Good to 3000F. The previous grease (CRC in the black bottle) had become sticky.

[kdauto]

Originally Posted by V3600

I also have a 3500 dually. I used to think it was my rotors but no more. The shuddering comes from uneven brake pad deposits on the rotors.

Last time I did my brakes I roughed up the rotors with wet sand paper to remove the brake deposits. I could have had them turned but I was curious how this would work. The old pads were put back on as they still had plenty of meat left on them.
Afterwards I took the truck out to burn in the pads. Old fashioned but it works.

I accelerate my truck to 45 mph then slow quickly to 10 mph and release the pedal pressure. Let the brakes cool for 30 seconds then repeat 3 or 4 more times. No more brake shuddering. No more need to turn rotors or buy new ones.

Also, the lube I use is Permatex Ceramic Extreme in the lavender colored bottle. Good to 3000F. The previous grease (CRC in the black bottle) had become sticky.

The rotor thickness variation RTV issue will come back again as soon as it is sollicited hard.

Beware with the purple/lavender Ceramic Extreme lube! I have a professional repair shop and was suckered into this stuff several years ago as it was "the best" That crap dried up and seized so many caliper pins they had to remove the mention to use on slide pins. It is OK on contact points and pad backings but I haven't dared try even the new formula which is supposedly better. I use the green lube they make which always worked fine and lasted 4 years on average up here.

[Hatchee]

UPDATE:
- Opened a case with GM
- They ask me to take to a second dealership
- Second dealership did recreate both front calipers failing to release properly while on the rack and test driving. Took them apart and said they were both contaminated. But they had no idea why.
- Replaced rear calipers, rotors, pads & fixed issue with parking brake
- Replaced front calipers (originals replaced at 37k), rotors, but they did not replace the pads because they were at 90%. First time that they would not repair under warranty, so it cost me $1800
- Drove 150 miles home and I could not touch the front wheels when I arrived home. They felt like a furnace.
- Drove to local dealer this morning and they got temperature readings of 413 & 408 on the front rotors
- Second dealer is talking to the factory rep to see how much of the $1800 I can get back. I might dispute the C/C charge.
- Both dealerships admit that they have no idea what is causing it and no idea what to try next.
- Waiting to here from GM re: what they are willing to do regarding a buy-back, trade, etc

Spoke to an attorney who specializes in Lemon Law in NC. He said that I'm SOL. GM knows what they are doing and it is now out of warranty even if the original issue @ 27k miles was never fixed.

[Itchytoe]

It looks like your brakes are dragging, so they are either mechanically stuck at the pads themselves, or the piston is applying a light pressure on them making them drag. It looks like you've had the calipers and modulator valve and rotors and pads replaced. There isn't much left in your braking system.

Have they checked out your master and slave cylinders? If either of them is sticking and not fully releasing pressure, it could result in your pistons always putting a little bit of pressure on the pads which would result in a drag.

[Hatchee]

Originally Posted by Itchytoe

It looks like your brakes are dragging, so they are either mechanically stuck at the pads themselves, or the piston is applying a light pressure on them making them drag. It looks like you've had the calipers and modulator valve and rotors and pads replaced. There isn't much left in your braking system.

Have they checked out your master and slave cylinders? If either of them is sticking and not fully releasing pressure, it could result in your pistons always putting a little bit of pressure on the pads which would result in a drag.

The second dealer did pressure tests on hoses, checked the slave & master and checked the modulator valve. This is a larger dealer and has more experience with 3500s. They have asked me to leave it with them for a week so they can bring in GM techs. I would certainly prefer having it fixed correctly than trading for a new one....even if they give me assistance on the trade, there is no way for it not to cost me more.

We were leaving for 6 weeks to New Mexico & Arizona in 2 days for our 1st long excursion

[okcnewbie]

I was going to vote for brake hoses. Supposedly if they are bad internally they can prevent the calipers from releasing correctly.

Thanks for keeping us informed.

[450Donn]

GMs are notorious for having brake issues. The factory stuff is pretty much junk. There are several online retailers that offer performance brake upgrades. Would be well worth it.
But brakes may not be your only problem soon. Depending on the exact fivers specs you could be borderline or really overloaded when hitched up.

[kdauto]

Originally Posted by Hatchee

The second dealer did pressure tests on hoses, checked the slave & master and checked the modulator valve. This is a larger dealer and has more experience with 3500s. They have asked me to leave it with them for a week so they can bring in GM techs. I would certainly prefer having it fixed correctly than trading for a new one....even if they give me assistance on the trade, there is no way for it not to cost me more.

We were leaving for 6 weeks to New Mexico & Arizona in 2 days for our 1st long excursion

Have you read my posts on RTV (rotor thickness variation)? I cannot believe they did all that and left the same pads!

Temp readings can be that high depending what you were doing, heavy braking, hauling etc.

Simply overpacking the caliper slide bushings with lube can cause brakes to apply a bit as they get hot. I have been guilty of this m,yself a few times over the years.

[Hatchee]

Originally Posted by kdauto

Have you read my posts on RTV (rotor thickness variation)? I cannot believe they did all that and left the same pads!

Temp readings can be that high depending what you were doing, heavy braking, hauling etc.

Simply overpacking the caliper slide bushings with lube can cause brakes to apply a bit as they get hot. I have been guilty of this m,yself a few times over the years.

I was also surprised that the pads were not changed this time but they have been all previous times. Independent mechanic inspected it for me and said everything seems to have been done correctly....except for the pads.

As far as what we were doing....I simply drove the truck slowly to the dealer. I drive with one foot and usually coast thru curves rather than breaking. By the time I got home, the rotors were not overheated. Not external factors.

The independent mechanic that I have consulted on this agrees with you but can not explain why it has happened time and time again. Once ok, twice maybe, 5 times....no way, especially since it is intermittent.

[arcaguy]

Something just hit me, has the brake fluid ever been changed completely? It seems like there is some kind of contamination is the braking system that is causing components to go bad. For all of the money spent by you and GM the entire braking system could have been changed by now. Something you might want to discuss with the dealer. Brakes just aren't that complicated and something rearing it's ugly head about every 20,000 to 25,000 miles. Just something to think about. Good luck.

[redhooker]

Yes, I would have them check both of the pumps to see if you have some type of a failure going on