Parking brake adjustment?

[DickWells]

What's the secret to taking up the slack in that lousy, so-called, automatic adjuster mechanism? I've gone through the Helm manual method of pushing forward on the cable, while someone stomps the pedal. Thought for a while that I had it, but it didn't pan out. The pads are hardly worn at all. These things are supposed to hold your truck, plus a trailer, facing up a hill, but I'll bet mine wouldn't hold the empty truck, right now!

[cowboywildbill]

I believe that there are still adustments on the backing plates. The main rear brakes are disk, but the parking brakes are shoes that ride inside the drums that are incorperated in the rotors.
They are hard to get to, I made an angled brake spoon from a heated and bent straight screw driver in orde to hit the star wheels. At least this was the case with my 02 3500. I haven't looked at our 07 yet, but I think they are still using the same axles and brakes. Maybe someone else can chime in and comfirm that. Hope that helps

[JohnC]

Didn't know you could get to them through the backing plate. the "approved" method is to measure the ID of the drum and the OD of the shoe. I forget what the difference is supposed to be. I just turn them up until it's a little tricky to get the disk on and that usually works.

[DickWells]

I forgot to mention that I had taken them up through the backing plates, just before I left VT. You're right, that's not the approved method, for whatever reason. The Helm manual says to take off the drum/rotor, and do the adjusting as described above, but it's not easy either. It also talks about doing this before you do the self-adjusting thing with the pedal. I'm just going by memory, of course, so some of this could be wrong, too.
Regardless, it's a PITA, for sure.
Thanks guys.:)

[MaxACL]

I have an '02 3500 and until last week I never had a parking brake. Oh there was one there but it was as useless as chicken manure on a pump handle. A year or two after I bought it (new) there was a safety bulletin that mandated a cable replacement because there is no adjustment. After that, instead of the pedal going to the floor, it would stop an inch from the floor and still didn't work.

Last week I had the rear brakes replaced and the parking brake works fine. I don't know what they did to fix them, the shoes were not replaced and the drum was not turned.

$560 for a rear brake job but hea... I have 360,000 miles on the truck and these were the originals. 320,000 on the original front pads. I'm not complaining, but it's sure nice having parking brakes with a standard transmission.

Mike

[DickWells]

Max: Thanks, I think you might have answered for both of us. The secret, I think, is to take the adjustment up with the wheels and drum/disks off, and on, while checking fit, just as the Helm manual says. I'm a long ways from those manuals, but if I can muster up enough gumption, I'll jack up one side, and remove the disk and see what I can do with it. I'm not hard up for parking brakes, it works with the empy truck, but with a load, I'm sure they would work like the chicken manure thing you mentioned.:D

[crashz]

I just went through this on my 1/2 ton. In MA we need to have annual inspections, and they check the parking brake. According to the inspector it needs to hold the truck in gear at 1200-1500 rpms. Not a chance. Even after replacing the brakes, it would barely hold above idle.

I still need to adjust the shoes a little more. I'd actually like to have a functional brake too!

[conway]

(I just went through this on my 1/2 ton. In MA we need to have annual inspections, and they check the parking brake. According to the inspector it needs to hold the truck in gear at 1200-1500 rpms. Not a chance. Even after replacing the brakes, it would barely hold above idle. )

Just curious. Is that for a diesel or gas engine? 1500 rpm on a diesel as we know is pretty high on the torque band.

Over here, as long as we have a big enough rock, we are" good to stay"

[crashz]

My truck is gasoline.

I wonder if MA has a different requirement for diesels? Obviously they should, but I wouldn't expect it.

[DickWells]

Mine passed the Vermont inspection in Sept., which entails stomping it on and running the engine up a little in D, at no specific RPM. Funny, but within a couple of weeks the darn thing was back to marginal. I had adjusted it the day before I took it in for inspection. You'd think that GM would have enough experience after a hundred years or so to makie a parking brake that actually works. Or can be adjusted, just like the ones they used to make, back in the good old days!

[cowboywildbill]

If you ever have a chance to see the rear rotors taken off, you will see how skinny and small these parking brake shoes really are. They aren't much. And one good run about a mile or so leaving them on by accident would probably make them pretty inefective.
I have parked on a hill before with a heavy load and the road was slick, I had to put the truck into 4 wd and set the brake. At least the parking pawl and all four wheels kept it from sliding. I don't think the emergency brake would have held the truck by it self even on dry road. And it was adjusted up pretty good.

[Frog]

I cannot believe how much has been going back and forth on several forums for several years on the parking brake problem on GM trucks.

My boss runs The Los Angeles Equestrian Center and recently asked me to adjust his parking brake on his 2004 GMC dually. At first I was put off a bit because there was no cable slack adjuster so I went to the back wheels which have disk brakes and upon inspection I could see the used the same practice as some other vehicles including my 1971 911 which is to use a small drum with shoes in the rotor.

The problem with GM is to make the pieces work the left or drivers side the star adjuster for the parking brake is at the bottom of the backing plate and on the right the plate is upside down so the star adjustment must be done on top of axle between the plate and the leaf springs I am sure this is the usual make what you have in the parts bin work.

The solution is adjust the left as normal moving the teeth on the star down to expand the shoes ad leave enough play so they don't drag. Now the kicker as Wild bill stated in his post you must make a tool by using a long screwdriver by measuring the distance from the star to the first 90 degree bend between the springs and backing plate then back from there far enough to clear the axle and make another angle down but it is not quite a 90 you have to play with it till you have the right angle to move the star up or down in this case up to tighten. That takes care of the shoe adjustment .

This got his parking brakes back but he split before I had a chance to figure out the foot peddle mechanism I beleive you can adjust the cable slack there also there is a small bar that seemed to disengage the cable wheel when you push down on it and I will figure that out when he gets back and post what I discover.

Folks we get thousands of these trucks at the Equestrian center every year and judging from the amount of complaints and the lack of answers to the problem of the parking brake I can make a fortune and buy a new GM dually for myself.

Roy