Something is sticking?

[DocBrown]

OK, weird title. I need opinions. I have not been driving my Sierra very often. It's for towing our travel trailer so it sits for weeks at a time. It has 153,000 miles and I'm trying to keep the miles off until we pay off my wife's Encore, then we'll replace the Sierra.

Last September I hooked it up to the trailer and when my wife backed it up she put the parking brake on. We always do that with the trailer. For clarity the Sierra has rear drums. At that point we had not towed for 3 months and had not used the parking during that time. I only drove the truck maybe 4 or 5 times during that period. The next day after hooking up, I pulled the trailer out and it wouldn't move. Then I got it go with a loud snap. I'm pretty sure the parking hung up. We didn't use the parking brake the entire week of that trip and had no issues. Nor any problems for the rest of fall and another camping trip. I was moving around on the street in front of the house every couple of days.

Fast forward to December and ice where I park the truck on a gravel pad. I had not driven it for about 3 weeks. Started the truck tried to move it. It would't move. I hit the gas hard and there was that loud snap. It was fine after that. I thought it was because the tires were frozen into the gravel. This past Saturday I wanted to use it to haul something. Same deal, tires frozen to the ground, wouldn't move, "snap" again.

I realized this morning that this is exactly what happened last Sept. But I have not used the parking brake at all since last August. Could this still be an issue where the shoes are still sticking after sitting for a while? I will not be able to pull the drum until it gets warmer out. If it is the parking brake, how do free up that cable?

Thanks for any thoughts on this.

 

[Sparky]

The parking brake simply mechanically applies the rear drum brakes, it isn't a separate brake.

I don't know what exactly would be sticking because as you drive you are using those brake shoes, and it isn't sticking every time you drive. Do the brakes feel normal?

It could be that the cable stuck slightly so the shoes are resting a little too close to the drum.

 

[littleblazer]

If I remember correctly, the parking brake apply is on a pivot arm with the cable. I would bet the moving linkage itself is binding up and getting it to move jerks the pad enough that the cable then snaps back. I've had it happen and actually that's how the parking brake cable snapped on the escalade. Also a rot in the line or a kink would do it too.

 

[DocBrown]

The parking brake simply mechanically applies the rear drum brakes, it isn't a separate brake.

I don't know what exactly would be sticking because as you drive you are using those brake shoes, and it isn't sticking every time you drive. Do the brakes feel normal?

It could be that the cable stuck slightly so the shoes are resting a little too close to the drum.

The brakes feel fine. I was thinking exactly that about the shoes and the drum. Using the truck I'm "exercising" the moving arts and they are fine. It's when it sits for weeks at a time that this seems to be a problem.

 

[Mooseman]

There's a spring at each cable end at the drums to pull the cables back. They are exposed and could have rusted off or are frozen (for winter). Sometimes there is also a pullback spring at the splitter that could also have gone missing. Then there's also cables that just go bad and rust. Best thing would be to go over the whole parking brake system.

 

[DocBrown]

You know it's interesting you mention springs. I was thinking about this on the way home last night after reading the above responses. I recall that in August I started getting this squealing noise that would come and go. I didn't think much of it at the time because it would sit for long periods and I wrote it off to rust since the brakes were working fine. I'm thinking like you, something broke and after sitting for a while the shoes spread and hold. Can't do much with it until it gets warmer. I'll try to remember to update this thread when I find out what it is.

Thanks guys!