2020 GMC Denali HD possible brake control module issue

Battery Frank · February 26

Started last summer towing my 34ft enclosed 3 axle trailer. 3 hours into a 4 hour drive the trailer brakes lock up for 2-3 feet....It felt like I had ran over something so I pulled over and checked everything out saw a wire hanging some off middle axle so I zip tied it up and figured that was the issue and continued towards home. Ten minutes later it did it again, but not as violent and seemed shorter so I slowed down and then it did it again a 3rd time so I pulled over again checked it out found nothing. didn't happen again the rest of the way home. I changed all my brakes and drums out on trailer thinking I hadn't maintained them and that was the issue. Then pulling my flat bed trailer it did the same so I figured it must be plug on bumper. 2 weeks ago it did it again towing nothing while driving 60 mph it locked up 2-3 feet then didn't do it again.

then the topper this last Friday 23rd it did the same 3 times in a row towing nothing while on freeway 1-3 mins apart. I have made some phone calls to dealerships and to an independent mechanic who all seem to think it's the "Brake Control Module" or possibly "air in ABS pump" has anyone had any of these issues happen to them before and if so How is GM not doing some type of recall on this. This truck is my work vehicle for my business and tows my race car operation, but NOW it is parked until remedied

NEED TO KNOW IF ANYONE ELSE HAS HAD THIS HAPPEN

Thank You for your input Frank

Edited February 28 by Battery Frank

newdude · February 28

On 2/25/2024 at 8:27 PM, Battery Frank said:

Started last summer towing my 34ft enclosed 3 axle trailer. 3 hours into a 4 hour drive the trailer brakes lock up for 2-3 feet....It felt like I had ran over something so I pulled over and checked everything out saw a wire hanging some off middle axle so I zip tied it up and figured that was the issue and continued towards home. Ten minutes later it did it again, but not as violent and seemed shorter so I slowed down and then it did it again a 3rd time so I pulled over again checked it out found nothing. didn't happen again the rest of the way home. I changed all my brakes and drums out on trailer thinking I hadn't maintained them and that was the issue. Then pulling my flat bed trailer it did the same so I figured it must be plug on bumper. 2 weeks ago it did it again towing nothing while driving 60 mph it locked up 2-3 feet then didn't do it again.

then the topper this last Friday 23rd it did the same 3 times in a row towing nothing while on freeway 1-3 mins apart. I have made some phone calls to dealerships and to an independent mechanic who all seem to think it's the "Brake Control Module" or possibly "air in ABS pump" has anyone had any of these issues happen to them before and if so How is GM not doing some type of recall on this. This truck is my work vehicle for my business and tows my race car operation, but NOW it is parked until remedied

NEED TO KNOW IF ANYONE ELSE HAS HAD THIS HAPPEN

Thank You for your input Frank

The trailer brakes are locking or is the truck locking the rear wheels up?

Edited February 28 by newdude

bruceb58 · February 28

Trailer brakes typically lockup if they get contaminated with grease when the grease seal fails. That's why you don't use the zerks at the end of the axle to repack the bearings...you do it by hand.

newdude · February 28

On 2/25/2024 at 8:27 PM, Battery Frank said:

Started last summer towing my 34ft enclosed 3 axle trailer. 3 hours into a 4 hour drive the trailer brakes lock up for 2-3 feet....It felt like I had ran over something so I pulled over and checked everything out saw a wire hanging some off middle axle so I zip tied it up and figured that was the issue and continued towards home. Ten minutes later it did it again, but not as violent and seemed shorter so I slowed down and then it did it again a 3rd time so I pulled over again checked it out found nothing. didn't happen again the rest of the way home. I changed all my brakes and drums out on trailer thinking I hadn't maintained them and that was the issue. Then pulling my flat bed trailer it did the same so I figured it must be plug on bumper. 2 weeks ago it did it again towing nothing while driving 60 mph it locked up 2-3 feet then didn't do it again.

then the topper this last Friday 23rd it did the same 3 times in a row towing nothing while on freeway 1-3 mins apart. I have made some phone calls to dealerships and to an independent mechanic who all seem to think it's the "Brake Control Module" or possibly "air in ABS pump" has anyone had any of these issues happen to them before and if so How is GM not doing some type of recall on this. This truck is my work vehicle for my business and tows my race car operation, but NOW it is parked until remedied

NEED TO KNOW IF ANYONE ELSE HAS HAD THIS HAPPEN

Thank You for your input Frank

Replying again in case you missed my first response.

Is it the trailer brakes locking up? Or is it the rear wheels of the truck locking up?

You say it did it towing nothing so it sounds like the truck is locking up the rear wheels.

Edited February 28 by newdude

newdude · February 29

On 2/25/2024 at 8:27 PM, Battery Frank said:

then the topper this last Friday 23rd it did the same 3 times in a row towing nothing while on freeway 1-3 mins apart. I have made some phone calls to dealerships and to an independent mechanic who all seem to think it's the "Brake Control Module" or possibly "air in ABS pump" has anyone had any of these issues happen to them before and if so How is GM not doing some type of recall on this. This truck is my work vehicle for my business and tows my race car operation, but NOW it is parked until remedied

NEED TO KNOW IF ANYONE ELSE HAS HAD THIS HAPPEN

Thank You for your input Frank

Frank, if you are still alive, your truck probably needs a transmission valve body. Its an internal issue which can cause the rear wheels of the truck to lock up when driving. Should be covered under your factory powertrain warranty if you are still within 5yr or 100k miles.

READ THE BULLETIN HERE - static.nhtsa.gov/odi/tsbs/2022/MC-10213229-0001.pdf

bruceb58 · February 29

3 hours ago, newdude said:

Frank, if you are still alive, your truck probably needs a transmission valve body. Its an internal issue which can cause the rear wheels of the truck to lock up when driving. Should be covered under your factory powertrain warranty if you are still within 5yr or 100k miles.

READ THE BULLETIN HERE - static.nhtsa.gov/odi/tsbs/2022/MC-10213229-0001.pdf

I thought his trailer wheels were locking up...not his truck rear wheels!

newdude · February 29

4 hours ago, bruceb58 said:

I thought his trailer wheels were locking up...not his truck rear wheels!

Initially he posted that but the later end of his story it did it without the trailer hooked up. That's what led me to post that bulletin. People have had the issue before on here and had the valve body replaced and it fixed it.

bruceb58 · February 29

3 minutes ago, newdude said:

Initially he posted that but the later end of his story it did it without the trailer hooked up. That's what led me to post that bulletin. People have had the issue before on here and had the valve body replaced and it fixed it.

The way I was reading it he was towing nothing on his flatbed trailer. Maybe he will come back and explain.

Battery Frank · March 28

On 2/27/2024 at 10:14 PM, bruceb58 said:

Trailer brakes typically lockup if they get contaminated with grease when the grease seal fails. That's why you don't use the zerks at the end of the axle to repack the bearings...you do it by hand.

I replaced all 6 drums and brakes also it did with flatbed attached also. then just recently it started doing the same thing without towing anything. I have ordered a new trailer brake module to be installed as soon as I can figure out where it is on truck...then I assume it will need to be programmed.

On 2/29/2024 at 2:02 PM, bruceb58 said:

The way I was reading it he was towing nothing on his flatbed trailer. Maybe he will come back and explain.

On 2/29/2024 at 2:02 PM, bruceb58 said:

The way I was reading it he was towing nothing on his flatbed trailer. Maybe he will come back and explain. Sorry for the long delay.....Yes it did it with flatbed with NO load and then it has just done it recently with NO trailer attached driving 55 down highway does 3 times about 500ft apart then doesn't do it again. Very nerve racking.

Battery Frank · March 28

On 2/29/2024 at 9:24 AM, bruceb58 said:

I thought his trailer wheels were locking up...not his truck rear wheels!

Bruce thank you for the reply....this has happened recently with nothing attached driving 55 on highway. It does act like it locks transmission up. seems to happen when braking then stepping on accelerator again is when it does it.