Brake booster pump pressure issue

benny12 · October 31, 2021

My wife was driving into the driveway last night when the brakes stopped working as they normally do, and she had come off the seat to push the pedal down before hitting the garage.

She is not thrilled with the truck, and after a google search on the issue, GM.

It has 58k on it, and last night was the first time this has happened. The recall for the booster issue was done over the summer. I am bringing it into the shop ASAP. The questions I have, primarily so I can get this fixed completely the first time, are:

1. Is this an intermittent issue? Will it happen more often now?

2. Is there proof of the issue (leaking booster pump, code, etc)?

3. What should be done by the dealer to fix it?

4. Is it worth noting the bulletin that is out there on the issue?

5. Being that is this is a known issue, is it on me to fix (I have the extended warranty to 100k, but have a deductible)?

For the record, my wife wants to sell the truck and never buy a GM again. She hasn't been paying attention to the market though...

JimCost2014 · October 31, 2021

21 minutes ago, benny12 said:

My wife was driving into the driveway last night when the brakes stopped working as they normally do, and she had come off the seat to push the pedal down before hitting the garage.

She is not thrilled with the truck, and after a google search on the issue, GM.

It has 58k on it, and last night was the first time this has happened. The recall for the booster issue was done over the summer. I am bringing it into the shop ASAP. The questions I have, primarily so I can get this fixed completely the first time, are:

1. Is this an intermittent issue? Will it happen more often now?

2. Is there proof of the issue (leaking booster pump, code, etc)?

3. What should be done by the dealer to fix it?

4. Is it worth noting the bulletin that is out there on the issue?

5. Being that is this is a known issue, is it on me to fix (I have the extended warranty to 100k, but have a deductible)?

For the record, my wife wants to sell the truck and never buy a GM again. She hasn't been paying attention to the market though...

Did they do just the computer re flash, or actually swap out the vacuum pump?

benny12 · October 31, 2021

Just the reflash.

movario · October 31, 2021

Had a similar issue. After I had replaced the vaccum pump everything worked again. Also had the recall, but there was just a reflash been done.

JimCost2014 · November 1, 2021

5 hours ago, benny12 said:

Just the reflash.

Push to see if you can have the vacuum pump replaced under warranty too. That is usually the problem.

What year is the truck, your mileage seems to be in a good spot for getting something done.

benny12 · November 1, 2021

30 minutes ago, JimCost2014 said:

Push to see if you can have the vacuum pump replaced under warranty too. That is usually the problem.

What year is the truck, your mileage seems to be in a good spot for getting something done.

2017.

When I sent my original post I had it in my head the powertrain warranty was 50k, now I realize it is 60k. So that helps. I just had to do the grill shutter replacement and that doesn't fall under powertrain, which caused my confusion. I feel a little better now, especially when it comes to a rental/loaner while it's being fixed.

JimCost2014 · November 1, 2021

9 minutes ago, benny12 said:

2017.

When I sent my original post I had it in my head the powertrain warranty was 50k, now I realize it is 60k. So that helps. I just had to do the grill shutter replacement and that doesn't fall under powertrain, which caused my confusion. I feel a little better now, especially when it comes to a rental/loaner while it's being fixed.

Search the site, there are posts about TSB's on the vacuum pump.

I have not followed all of them, so not really sure if any have been revised, or what years/models they are covering, but if you do not ask the questions, you will never know the answers

mikeyk101 · November 1, 2021

Recalls are recalls no matter what the mileage is or age of vehicle. If a recall is put out, it has to be covered by the company at their cost. It is usually a safety issue and is a liability to the company if it isn't corrected just like the whole air bag fiasco. Any vehicle at any age that had those air bags was covered.

I had the initial recall flash done a while back during an oil change. I don't even think I had a choice in the matter but didn't care either way. Up to that point, I hadn't had any issues. Then some time after this, I too suffered from the hard brake pedal. It happened the first time when I was reversing out of my driveway which has a slight grade to it. It happened a few other times while going forward after that. Scared the hell out of me because I thought I was going to rear end someone on one of the episodes. I got it to the dealer right away and they diagnosed a bad booster. It got replaced, no problem and at no cost to me.

Sorry, I just read a little further on the recall and all that was mentioned was the reprogram of the module. But I know I pressed the issue when it happened after the flash and I got my booster replaced after the dealer determined it had failed.

And I just checked my service history. The reprogram was done of my 2016 on Oct 2019 at 39,000 miles. I had it in dealer with the complaint for the hard brakes in Dec 2020 and my miles were at just over 51,000

Edited November 1, 2021 by mikeyk101

Grumpy Bear · November 1, 2021

1 hour ago, mikeyk101 said:

I don't even think I had a choice in the matter but didn't care either way.

Dealer never sees my truck. That's how I 'have" a choice.

The problem was the pump oil screen was to fine for the OCI and oil recommended. The screens plugged and the pump lost vacuum forcing oil into the booster and killing it dead. They revised the pump BUT only replaced the pumps upon failure...which means a brake failure. So as the claims piled up the band-aid re-flash of the ABS module, which is much much cheaper than a pump replacement was thrown against the wall and it stuck. I change oil more often and use a better oil than required. Pump has 150K miles on it which was the STATED limit of liability for the part. Still pulls top of the range vacuum. Still brakes like a beast. Still has over 50% of the pad left and the rotors are mint. I'm not letting them mess up the best set of brakes I've ever had on any vehicle at anytime because the masses don't like to change oil.

They are attempting to make this idiot proof, spending zero money and never actually fixing anything at all but their liability for the damage.

Got one more recently that states my A pillar air bag can kill me BUT they don't have parts to fix it and will get in touch when they do. Now they never say. "you need to park it"...... But sending the memo lets them off the hook doesn't it? What a joke.

benny12 · November 2, 2021

I got an appointment for Thursday. To answer some of my questions above, for future reference:

- This is warrantied for 10 years, 150k (I still wasn't able to get a loaner/rental though because they sold all their loaners)

- The bulletin was not needed, the service guy that answered the phone knew what needed to be done when I said I was having the booster pump issue

- He said a code is thrown when it happens

The biggest problem is my wife, who drives the truck regularly, is absolutely livid that GM can do this and all the supposed government overseers are allowing this to happen. I find it hard to believe that Ford, Ram, Toyota, Nissan, etc. would handle this problem any differently, but they haven't manufactured a vehicle for me yet that the brakes don't work occasionally so I can't confirm.

It would be nice to have some confidence that this wont happen after its repaired, or at high speed. But then she read about the 2020 Equinox. And then the Volt/Bolt fiasco...

JimCost2014 · November 2, 2021

5 minutes ago, benny12 said:

I got an appointment for Thursday. To answer some of my questions above, for future reference:

- This is warrantied for 10 years, 150k (I still wasn't able to get a loaner/rental though because they sold all their loaners)

- The bulletin was not needed, the service guy that answered the phone knew what needed to be done when I said I was having the booster pump issue

- He said a code is thrown when it happens

The biggest problem is my wife, who drives the truck regularly, is absolutely livid that GM can do this and all the supposed government overseers are allowing this to happen. I find it hard to believe that Ford, Ram, Toyota, Nissan, etc. would handle this problem any differently, but they haven't manufactured a vehicle for me yet that the brakes don't work occasionally so I can't confirm.

It would be nice to have some confidence that this wont happen after its repaired, or at high speed. But then she read about the 2020 Equinox. And then the Volt/Bolt fiasco...

Had the vacuum pump replaced at 59500 miles on our 16 Tahoe (wife's rig) , approaching 95000 miles now without the issue returning.