Hi all,

I’m sure this is a commonly asked question but I still honestly have no idea how drum brake adjustments work lol.

i currently have the drum shoes setup where there’s barely drag on the drums when you rotate them, and the parking brake cable is pretty tight when it’s on, but for some reason even on a small incline the parking brake cannot stop the truck from rolling backward.

is this just some inherent flaw with drums or am I doing something wrong here?

 

The p-brake cable should not have very much slack when the parking brake is not applied..... and the cables DO stretch over time. Of course, the adjuster is under the vehicle, thus, exposed to all the nastiness on the road, and after a few years, trying to adjust it, is a losing battle.

Find the adjuster, drown in it penetrating lube for a couple days, clean it up as best ya can.... (wire brush) drown it a couple more days, then try and adjust it so the cable has as little slack as possible. See if that doesn't improve its attitude any.

 

I actually was lucky enough to have a not completely baked in rust tensioner and I have tightened it super tight, and the cables are brand new as well, well as of a year and a half ago.

My dad was thinking it could be that only one pad touches the drum when the parking brake is applied which would make sense.

Due to my new exhaust routing, the factory tensioner was touching the pipes and clanging around so I got rid of it and, if you’re familiar with the layout of the first gen Dakotas, got rid of the “hook” on the torsion bar crossmember and replaced it with a hook bolt and am using that as the tensioner. This is all to get the cable off of the pipes, but it was still a problem prior to this “modification”, which I did today.

 

I *think* you are correct, in that only one shoe actually does the braking for the parking brake, and I believe it is the front shoe... which should be shorter pad area, than the rear shoe. (the fronts are self-energizing when you actually step on the brake, friction tries to drag it harder into the drum.) Might explain why it will still roll backwards fairly easily... But, one would think it *should* be more effective than that.....

Also, keep in mind, new cables will stretch some as well.....

 

fair point, I think when I have the time and the will I’m going to tension the cable more, probably have to get a hook bolt with more thread or get a die and make more thread, and then readjust the shoes again.

It’s very odd how unbalanced the holding power is. At idle, if the brake is on and I let out the clutch in first it will die before it moves, but if I’m on even a slight incline it rolls backward full brake.

 

That's the 'self-energizing' thing rearing it's ugly head.

 

Seems like it lol, maybe I’ll suddenly just have a Jeep GC rear end with discs and never have to deal with drums lol. At least in terms of main brake drums, I think the GCs still have drum parking brakes. At least the ZJs