Parking brake (yes, another one!)

[Larryjb]

Every parking brake system I have ever had, the pedal actuator will go down until the the brake is fully applied, and the resistance is enough that you cannot press the parking brake to the floor even if you tried.

My 2002 Tahoe has never been like that, so I always figured I didn't have the parking brake adjusted properly somewhere. I took another attempt today at it, replaced the parking brake shoes again, but also replaced the rear disks. I adjusted the parking brake shoe until i could not quite get the disk brake onto the shoes, then backed it off a 3-4 notches. I know that you are supposed to measure the spread of the shoes. However, even after doing this adjustment, my parking brake pedal still goes to the floor.

Is it designed this way? I have yet to see how well it holds, as I'm not quite finished putting things back together.

 

[Scottydoggs]

mine dont hit the floor. ive done the rear rotors and adjusted the e brakes to a light drag. like you could hear it scrape in one area as it spun.

 

[S33k3r]

Maybe you need to replace the cable?

 

[B-train]

Maybe you need to replace the cable?

This^^^^^ and how muscular is your left leg? Might want to try just a slow apply on a slight hill until the truck stops and see where you're at. It's a good possibility the cable may be stretched. I've seen guys just mash the shit out of them on a normal basis thinking that's how they work

 

[Fless]

2002 may have the older style threaded rod on the end of the intermediate cable -- is that getting adjusted? It's outside of the frame under the driver's side doors.

 

[Larryjb]

@B-train, I'm not a muscular guy by any means! On my wife's Explorer there is a solid resistance about half way down when applying the parking brake. I might be able to push it down more if I really tried. It holds solid.

@Fless, I'm aware of that intermediate cable with the threaded rod. That cable snapped on me a few years ago. It is adjusted properly.

I took the wheels/calipers off again tonight and got about another 15 clicks each side. It seems that the new parking shoes needed bedding. It was a lot easier to fit the shoes to the inside hat of the disk. I've adjusted it so that there is a little resistance to turn each disk (with the opposite disk removed). The parking brake now holds more solidly, but I could probably push the parking brake pedal down to the bottom if I tried.

Now, the big difference between GM/s parking shoes and Fords is that GM has a one piece horse-shoe style, whereas the Ford parking shoes are more like the traditional drum brake shoes. GM's would take more force to spread, so maybe the parking brake pedal has more mechanical advantage built in to it. Also, there may be a spring relief mechanism built into the pedal mechanism to prevent overstretching the cable. I did have to replace the pedal mechanism once because the casting actually cracked.

I may make one more adjustment in the spring time when I switch back to my all-seasons.

 

[lyncht1967]

My money is on loose cables..there is a fix in forum post link below. it utilizes a spacer to allow more travel of rod/cable through adjuster bracket under bottom of truck. a stack of nuts with an inner diameter large enough to slide up and down threaded rod will also work in lieu of spacer.

Parking Brake Adjustment - Truck Forums

Chevy Silverado/ GMC Sierra Forum - Parking Brake Adjustment - Well today I went ahead and put all new brakes on my 1500HD truck. I went ahead and bought the new parking brake shoes (this truck has the rear disk brakes with the drum style parking brake). My question is has anyone figured out an...

www.truckforums.com

 

[Larryjb]

My money is on loose cables..there is a fix in forum post link below. it utilizes a spacer to allow more travel of rod/cable through adjuster bracket under bottom of truck. a stack of nuts with an inner diameter large enough to slide up and down threaded rod will also work in lieu of spacer.

Thanks, I remember reading about this fix years ago. In my case this isn't the problem. I have lots of adjustment left on the adjusters at the brake shoes. My problem is that once I have them adjusted so that they are just touching the inner hat, the parking brake pedal doesn't feel as firm as I would like it to be. If I were to add spacers as in the picture, the parking brake shoes would be definitely rubbing.

I'll see how it goes, and make another adjustment in the springtime.

And you know that clip that is supposed to hold the shoes in place when installing the disk? Some one before I owned the truck stripped out the bolt that holds the clip in place. I have to do wheel bearing in the back, so I'll drill and either retap for a larger bolt or see if I can find a Timesert that works. If I'm pulling the axles, I want to go for the best solution there, but that's for another day.

 

[Fless]

If you pull the axles, use the one-piece (OE) backing plates. I think they're thicker than the Dorman 2-piece ones.

 

[lyncht1967]

Thanks, I remember reading about this fix years ago. In my case this isn't the problem. I have lots of adjustment left on the adjusters at the brake shoes. My problem is that once I have them adjusted so that they are just touching the inner hat, the parking brake pedal doesn't feel as firm as I would like it to be. If I were to add spacers as in the picture, the parking brake shoes would be definitely rubbing.

I'll see how it goes, and make another adjustment in the springtime.

And you know that clip that is supposed to hold the shoes in place when installing the disk? Some one before I owned the truck stripped out the bolt that holds the clip in place. I have to do wheel bearing in the back, so I'll drill and either retap for a larger bolt or see if I can find a Timesert that works. If I'm pulling the axles, I want to go for the best solution there, but that's for another day.

Ahh, i see. Well, the loose cables are a common fail so hopefully it will help others that end up on this post tracking that problem. Good luck on your quest. I had it and my co-worker had it and spacers tightened things right up.

 

[S33k3r]

Is it possible you have a spot where the cable is binding, but not in sight? Also, could you have a bad pedal? Just grasping at straws...

 

[Larryjb]

The parking brake appears fine for now. I could probably force the pedal down more, but it holds just fine for now.

I think the first time I adjusted the parking brake, the shoes needed to be mated to the drums properly. As soon as I went back to it a couple of days later I was able to get the adjustment much better.

I replaced the entire parking brake mechanism a few years ago, but never got the parking brake adjusted properly. I think I've got it this time.

 

[Larryjb]

Well, the parking brake has worked well until we got a freeze, lows to -13°C for a few nights. I used the parking brake out of habit, and now the mechanism appears to be jammed on the right rear. In the picture you can see that the level has not returned to its completely released position. It has warmed up enough that ice shouldn't be the issue now, so I suspect that something shifted mechanically. Any ideas?

I will be pulling the parking brake shoes off next, and disassembling the adjuster next. I may have to pull the cable right out from the lever and reposition it, but I hope I don't have to go that far.

 

[Fless]

I agree that the lever on yours isn't fully returning.

Mine's an '04 so I don't know if the cables attach in a different orientation, but the few cable hooks I've seen (on the passenger side) hook from the bottom up. That has to do with the bracket orientation on that side. Confirm that the return spring isn't contacting the axle tube; your pic is a bit fuzzy so hard to tell.

If there's no tension on the cable those aren't usually very difficult to pull out of the lever.

Pic of mine:

 

[Fless]

To add, to get the hook out the cable needs to come out of the bracket.

 

[Larryjb]

@Fless thans for that, and the picture.

It seems that the lever that goes through the backing plate may have dislodged from the pill that connects to the adjuster and brake shoe. Perhaps when I last released the parking brake, the shoe didn't return as fast as the cable and that pill got lodged? Anyway, i've got it back together now and working. I lubed the heck out of the lever and inside the adjuster to try to prevent freezing again.

Big dilema now, if I am parked on a slope in the freezing weather do I use the parking brake or not? If you have ever locked your transmission without the parking brake you will know what that headache is like. And don't tell me to just yank harder on the shifter. My wife broke the column shifter doing that once. Even bigger headache!

 

[Larryjb]

To add, to get the hook out the cable needs to come out of the bracket.

Yup. Did that already, but I don't think I set the hook as you described because I'm reading this after I got it put together. But I'll remember to reposition it when I put my all seasons back on.

 

[Larryjb]

Well, the passenger side parking brake froze again. It seems to be a sluggish cable. I exercised the parking brake 20 times and it released finally. I think I replaced the intermediate and DS parking cables. I guess the PS is next.

 

[Fless]

Depending on age and rust, getting that intermediate cable disconnected from the front cable can be a bugger.

 

[Larryjb]

Depending on age and rust, getting that intermediate cable disconnected from the front cable can be a bugger.

I had that fight a few years ago. The passenger rear cable should be fairly easy. I can get it off the lever from the backing plate easily. It will mainly be feeding the cable through to the wheel.

I had trouble with the parking brake freezing a few years ago as well. I don't know why I didn't change out the rear right at the same time. Perhaps I had to fight so much with the intermediate cable, and replacing the rubber grommet through the backing plate was no fun either. I now have te 2-piece backing plates so removing that might make replacing the grommet easier if I choose to replace that.