Brake failure

[Madcircle]

Hello. So today on the way to pick my wife up from surgery, I came off the highway and on the off-ramp, I had no brakes. Scary as $#!T, but pressed as hard as I could until I stopped. The grind was wicked. Made it to the hospital going slow, but the brake system was dead.

I've had 2 Brake Pump replacements. 9/2021 and 11/2025.

What causes this? Why, out of nowhere does it happen? No warning lights, no leaking, no smell... Thanks.

2017 Chevy Tahoe LT V8 4x4
97000mi.

 

[TheBigCheezeBall]

Hello. So today on the way to pick my wife up from surgery, I came off the highway and on the off-ramp, I had no brakes. Scary as $#!T, but pressed as hard as I could until I stopped. The grind was wicked. Made it to the hospital going slow, but the brake system was dead.

I've had 2 Brake Pump replacements. 9/2021 and 11/2025.

What causes this? Why, out of nowhere does it happen? No warning lights, no leaking, no smell... Thanks.

2017 Chevy Tahoe LT V8 4x4
97000mi.

Was this failure the same as your other failures? I lost a master cylinder on a 1989 Toyota Camry when I was 16. Had nothing except the emergency brake and down shifting. Never had a brake pump fail though. Could there be trash in the system?

 

[Madcircle]

So what I have researched, is that its called "Stiff Brake" and caused by Brake Vacuum Pump failure. Apparently 2016-2018 Tahoes are famous for this issue, and there is a long standing warranty (Until 2027) to get it fixed at no charge when ever it happens. My mechanic said a belt broke, and that it could affect the Brake Pump. Regardles, it was something i would never want to experience again while I am driving.

 

[Doubeleive]

So what I have researched, is that its called "Stiff Brake" and caused by Brake Vacuum Pump failure. Apparently 2016-2018 Tahoes are famous for this issue, and there is a long standing warranty (Until 2027) to get it fixed at no charge when ever it happens. My mechanic said a belt broke, and that it could affect the Brake Pump. Regardles, it was something i would never want to experience again while I am driving.

I believe some have changed it back to engine vacuum, I wonder if a T and a couple check valves could be installed as a redundant system

 

[Madcircle]

Was this failure the same as your other failures? I lost a master cylinder on a 1989 Toyota Camry when I was 16. Had nothing except the emergency brake and down shifting. Never had a brake pump fail though. Could there be trash in the system?

Yes. I have discovered its the Brake Pump Vacuum System, and there is a 10-year Special extension warranty to replace it if it fails in that timeline. That ends next year(2027). And yes, the emergency brake was my friend.

 

[Madcircle]

I believe some have changed it back to engine vacuum, I wonder if a T and a couple check valves could be installed as a redundant system

Thanks for your reply. Sorry if I sound dumb, but are you saying the brake vacuum system could be swapped out for an Engine Vacuum? Ill have to look into that. I was hoping to keep this car for another 3-5 years, but I definitely don't feel 100% confident driving it anymore...

 

[Doubeleive]

Thanks for your reply. Sorry if I sound dumb, but are you saying the brake vacuum system could be swapped out for an Engine Vacuum? Ill have to look into that. I was hoping to keep this car for another 3-5 years, but I definitely don't feel 100% confident driving it anymore...

easy enough, the v4 mode has to be disabled

 

[OR VietVet]

Yes. I have discovered its the Brake Pump Vacuum System, and there is a 10-year Special extension warranty to replace it if it fails in that timeline. That ends next year(2027). And yes, the emergency brake was my friend.

It is called a parking brake, except in your case it was an emergency brake.
Long time ago, on a 64 Chevy pickup, had no brakes on an off ramp. Down shifted and no park/emergency brake. Got it stopped a 1/4 mile down road. My butt ate some seat cover that day. In Mo. and salt on roads. Rusted brake line. It was a HAIRY HAIRY experience.

 

[Fless]

The TSB:

N182202780 GMC Technical Service Bulletin

N182202780 GMC Technical Service Bulletin

www.tsbsearch.com

 

[Madcircle]

The TSB:

N182202780 GMC Technical Service Bulletin

N182202780 GMC Technical Service Bulletin

www.tsbsearch.com

Yes. This is the Special Coverage Warranty that my vehicle is currently receiving at the dealership. Contrary to the description, I was travelling at a high rate of speed (65-70mph) and no warning lights went off. That's what makes me nervous about driving the vehicle. I use it for work and travel highways all the time. Had I been in busy traffic (I live in CA, it's a real thing) serious damage and potential serious injury could have happened. Anyway. Thanks to you all for your responses.