I have a 2003 Yukon XL SLT 5.3 liter, automatic transmission, 4 wheel drive.
Miles: 217627
I had some noise coming from the right rear wheel. When I inspected it I found the brake pads had worn down to nothing and the inside of the brake disk had a lot of wear.
I inspected the pads on the left rear also and found hardly any wear on them or the disk. I replaced the pads and the disk on that wheel also since I had taken them apart. So now I have new brake pads and disks on both rear wheels.
When I inspected the front brakes (Left and right) they looked only lightly used, practically new.
When I took the truck for a test drive, the noise was gone and the brakes seemed to be working. I only drive about three miles to work on city streets so I'm not doing a lot of hard breaking daily.
I had to drive up into the hills the other night and on the way down the right rear brake was making a scraping noise when I applied the brake and after I released the brakes.
It was obvious that the front brakes were not engaging until I was about halfway down the hill, and the scraping noise stopped from the right rear brake at about the same time the front brakes started to engage.
This problem is intermittent. When I apply the brakes here in town, I can hear a light scraping noise coming from the right rear wheel about half the time, then it fades out.
It doesn't seem like the front brakes are engaging all the time.
Troubleshooting: I get in the truck and without starting it, I pump the brake pedal slowly. By the fourth pump, the pedal is hard to push down.
Then I start the truck and push the brake pedal and it is very easy to push down, it doesn't provide much resistance no matter how many times I pump it.
Summary: The short version of the problem is, that when my front brakes do engage I have no noise from the right rear brake, but most of the time it seems like it is only the right rear brake that is stopping my truck and when it does, there is a lag between the time I take my foot off of the brake peddle and when the scaping noise stops.
You are my last hope. So far I have gotten five different opinions from five different people. I need to get this fixed.
Thanks for your help.
Paul0341
Maybe jack up a front wheel. Start the truck and have somebody hold the brake pedal down as you try to spin the front tire.
If you can't spin it, the brakes are working.
This sounds more like a bad caliper on that right rear causing the brakes to drag on that wheel. So it's wearing them out
Your left rear caliper is probably stuck and not working. (Either that or the brake hose on that caliper is plugged up inside.) Not a surprise after more than 20 years, assuming those parts are original, especially if brake fluid has never been changed.
@chucktobias Do you mean my RIGHT rear caliper?
Thanks for the quick response.
@paul0321 Whichever is not working. However I'd replace both if that's what's happening.
@chucktobias O.K. Thanks. Looks like I'm headed to O'Reiley's. LOL
I have one more question. When braking, what brakes are the primary stopping brakes? Do the rear brakes do most of the work and only the front brakes kick in when the ABS is activated?
@paul0321 Front brakes do about 80% of the work. The function of ABS is to prevent skids. (The early systems were actually referred to as "anti-skid" systems.) You may need a bidirectional scan tool to bleed the brakes. It depends on the ABS system. I've found on my car it's not needed unless you get air into the ABS module. When I replaced my rear calipers earlier this year I didn't have to do anything special to bleed them. (Your mileage may vary.)
@chucktobias O.K. So why do my front brakes have so little wear on them but that right rear brake is doing all the work?
@Paul0321 I am assuming the hose is clogged up if brake fluids were mever changed.
O.K. So why do my front brakes have so little wear on them but that right rear brake is doing all the work?
There are a lot of variables. For example, maybe the pads are a hard material that doesn't wear as quickly. Or maybe your 21-year-old front calipers and hoses are not working optimally either.
Don't take my word for it, do a little research regarding how much braking force is supplied by the front versus rear brakes on most vehicles. If your right rear brake were the only thing working you'd have hardly any braking power at all.
@chucktobias O.K. Thanks. I believe you, it's just that I know practically nothing about how brakes work, or the rest of the truck for that matter. I'm just trying to get a better understanding of what's going on when I hit the brakes.
Thank you for your patience and quick responses.
@paul0321 No problem, I can certainly be mistaken about things and it's always good to do an online search for confirmation. That the front brakes do most of the work on the vast majority of vehicles is pretty firmly established, but there can be exceptions.
@chucktobias O.K. Now I know. Thanks again.