Truck Brake issues....

[haoleboy]

Does anyone recommend a good repair shop in S. Md?
My 2015 Silverado is having some brake issues. I noticed it a few weeks ago when I was putting my boat in the water. On the ramp, I heard a noise that I can only describe as the brake rotor slipping past the pads/caliper. This noise only comes from the driver side rear, and when I'm holding brake pressure, the pedal slowly goes towards the floor.
I've checked all 4 wheels and the brake lines that I can see, also under the hood near the master and booster. I can't see any leak what so ever.

I don't want to be the "qualified captain" and have my boat, trailer, and truck in the water at the same time.

I'm open to all suggestions, and or recommendations on repair shops.

 

[Wsanner]

Look into a recall for GM vacuum pumps. I have ran across a few trucks with different brake issues and this has been the culprit

 

[jr88]

From past experience, if pedal goes to floor but no loss of fluid (Is level OK in Master Cylinder) then its the check valve in the Master Cylinder, not too bad or costly to replace

 

[Johnconlee]

Guy motors in Mechanicsville

 

[hobiecat590]

Lary's Auto Repair in Lusby.

 

[Boss94]

Prolink in Prince frederick has been working on my trucks since 2000. does great work and affordable.

 

[haoleboy]

youtube to the rescue. I did some google searches and found some people with the same problem. The creaking sound from rear brakes usually comes from sticking caliper guide pins. I'll take both my rear brakes apart, clean and lube, and report back.
Thanks for the ideas, guys.

 

[Zaicran]

youtube to the rescue. I did some google searches and found some people with the same problem. The creaking sound from rear brakes usually comes from sticking caliper guide pins. I'll take both my rear brakes apart, clean and lube, and report back.
Thanks for the ideas, guys.

Right on, let us know how it goes….

 

[haoleboy]

Well, I swapped the caliper pins and bushings. Cleaned and regreased the caliper bracket. Cleaned and adjusted the parking brake shoes.
Noise is still there, and the brake pedal still slowly goes towards the floor while trying to hold pressure on the pedal.

I'm at wits end. Guess I have to bite the bullet and take it to a mechanic.

 

[Outerlimits]

Collier Auto Repair LAPLATA
Tommy is a good guy and a 2A supporter, shop is at his house on Stage Coach Rd

https://www.mapquest.com/us/maryland/collier-auto-service-369391789

 

[antco]

Creeping pedal like you're describing is in the master cylinder.

 

[fnfalsar48]

Creeping pedal like you're describing is in the master cylinder.

Don't be so sure... how about the abs pressure modulator valve?

 

[haoleboy]

So, I installed a new master cylinder yesterday. Same issue, creaking noise from the left rear, and slow creeping pedal.
If the caliper is bad, and fluid is leaking past the piston, I would see the leak right? Still nothing, no leaks from anywhere in the truck.

I feel like I should replace the caliper since that is where the noise is coming from, and when I hear the noise, the pedal creeps. Maybe should have started there first.

 

[DadOSix]

Are you rolling or standing still as the pedal creeps away?

My 06 duramax had a habit of falling pedal while at a 'slow roll' Ie - stop light and a bit of drift had the pedal falling away.

Tried the usual culprit - master cyl - no joy. Turns out I had a bad ABS wheel speed sensor and the ABS computer 'thought' that wheel was locked up, when every one else was showing motion, and decided to pulse the brakes.

Dealer could not find it, but after a year or so, I was able to clear it up.

 

[haoleboy]

Standing still. I first noticed it at the boat ramp. Made me pucker a little when I was putting the boat in the water and the pedal started to creep. The truck didn't move, but it still made me nervous.

 

[jrumann59]

Maybe a bad brake hose from the steel line to the caliper. Have someone moosh the pedal and see if there is bulge somewhere on the "rubber" line from the caliper to the steel brake line going back to the master cylinder.

 

[DadOSix]

Standing still. I first noticed it at the boat ramp. Made me pucker a little when I was putting the boat in the water and the pedal started to creep. The truck didn't move, but it still made me nervous.

Couple more ideas - as I hate firing the parts cannon at a problem.

1- you stated above that you checked all the lines and rubber that you could see. Sometimes a pinhole leak will develop ina place you can’t see - say like over the frame rail, behind the fuel tank. 06 blew a brake line from rust thru whilst plowing snow once. Linda fun to plow with only partial brakes.

2- the hose could bulge as above . Sort of like an aneurysm, foot on pedal, hose pressurizes, bulges out, pressure drops, pedal falls.

Just for fun, if you have one of those point and click thermometers (ir), take a drive and get them brakes warm. Check the wheel / brake temps when warm. 3 hot, 1 cold - cold caliper is not working. 1 hot 3 cold - hot caliper is sticking.

 

[Johnconlee]

Couple more ideas - as I hate firing the parts cannon at a problem.

1- you stated above that you checked all the lines and rubber that you could see. Sometimes a pinhole leak will develop ina place you can’t see - say like over the frame rail, behind the fuel tank. 06 blew a brake line from rust thru whilst plowing snow once. Linda fun to plow with only partial brakes.

2- the hose could bulge as above . Sort of like an aneurysm, foot on pedal, hose pressurizes, bulges out, pressure drops, pedal falls.

Just for fun, if you have one of those point and click thermometers (ir), take a drive and get them brakes warm. Check the wheel / brake temps when warm. 3 hot, 1 cold - cold caliper is not working. 1 hot 3 cold - hot caliper is sticking.

The ir thermometer after a road test is a very good idea.

 

[OldBrokenGrunt]

KISS principle.
Is the fluid low on the reservoir? No means no leaks.

 

[haoleboy]

To be honest, I only checked the rear hoses since that is where the noise is coming from. Both look to be in perfect shape.
The fluid level in the master has never changed. No signs of a leak anywhere.
I do have a laser thermo, I'll do a road test and check the heat on the rotors.