For the past week or so I've noticed a strange rubbing sound coming from the rear whenever I am reversing out of driveways etc. For whatever reason I can only really hear the sound when I'm backing up though. I have a feeling its a sticking caliper but I'm just not certain. I'm pretty confident that I can feel it dragging my truck a little bit during acceleration as well so I had to make an appointment for tomorrow to get it checked. If it is in fact the caliper sticking I wouldn't want to be burning up pad. Hopefully it will be a simple fix...

Why I have the thread open, would any of you guys know what would cause my truck to make a hissing noise from inside the cab when the defroster is on in my truck? Even when I turn it off I can still hear it making a hissing noise.

 

Vacuum leak or refrigerant flowing thru the evaporator.
Could be the parking brake rubbing inside the rotor.

 

press your parking brake all the way in and then release it....try that might just be hung up....

 

Okay will do tonight, thank you!!

 

To ease your mind with the caliper-drag/sticking possibility. After you take a short drive, using the brakes several times. Walk around and touch each hub to feel if any is much hotter than the normal warm ones.
Severe dragging, one will smell the burning pad before you blister the fingers on the hub.

 

i have this exact problem- I am almost positive its the rear parking pads. I replaced my parking shoes and put new rotors- noise went away for abit. It seems like the noise comes on more when there is moisture from rain/snow. I then sanded the inside of the rotors to get rid of the rust and adjusted the shoes to be as loose as they can be. No noise for a few weeks- then it snowed/rained and bam noise again. I then sanded the rotors and adjusted them until they had a slight drag and then backed it off alil- no noise again for a few hundred miles until there was moisture and then the noise came back. Im about to giveup and give it to a shop. Spent hours upon hours searching and found alot of the same problems with no soultion. Lemme know if someone has an idea? mine is a 04 qc 5.7 4x4

 

I had the same problem, but I replaced the brakes and rotors and now no more embarrassing screech.

 

Same thing here as well. Happens when its rainy/snowy/cold. I just installed new pads and rotors about two months ago. Just about every morning when i pull out of the drive for work, it will make a mmmmmmmmm mmmmmmmm noise as if the pads are sticking. It does it until the end of the street, and after i have applied the brakes to kind of rub the buildup of the rotor it doesnt make the noise anymore during the drive.

 

what does everyone think- is it the parking brake or the actual rear brakes. I know I had this problem intermittently with the stock brakes a few years ago but it was mostly when it was wet. I just replaced my pads/rotors and the noise started getting more common about 4-6 weeks after that. Im thinking its the parking brake. Ive seen this post on a number of forums but havent been able to pinpoint whats the cause.

 

anyone else have any ideas? thanks