Parking brake star adjusters will not stay tight

[Rdonahe]

Hello all. I searched for this and see plenty of threads on how to adjust, but could not find any on this specific issue.

I have had my rear rotors off, inspected parking brake shoes and I have meat on the bone and they are within spec. I also cleaned up the hardware as best as I could. I then reinstalled the rotor and adjusted the star adjusters until I got significant drag turning the rotor by hand. I then backed off the star adjuster a couple clicks to where I could turn by hand and feel slight drag. Tested the parking brake at this point and it worked fine. Not amazing but it was holding my rig stopped in neutral on a slight incline.

The problem is the adjusters seem to be backing themselves out as over time the effectiveness of the parking brake diminishes until it is no longer doing anything.

Is there a trick to get the adjusters to stay in position?

Thanks in advance.

 

[discoverydave]

Had this same exact issue on a 92 FJ80 I was working on last year. The star adjusters backing off is almost always one of two things — either the adjuster wheel itself is worn enough that it won't hold its position against the return spring load, or there's contamination (dust, a bit of rust, old grease residue) preventing the teeth from seating properly between clicks.

Pull the adjuster out entirely and have a good look at the teeth. If they're rounded off or you can't feel a positive click when you wind it by hand, the adjuster is shot and needs replacing. They're cheap, so if there's any doubt just swap it. Also clean the adjuster threads with a dry brush — never grease the threads, just clean metal. A tiny bit of anti-seize on the threaded rod only, nothing on the wheel teeth or the shoe contact point.

The other thing worth checking is whether the cable itself has any slack in it after adjustment. Even a properly set adjuster will walk back if the cable is stretching slightly under repeated use and the shoes are taking a set. Pull the parking brake lever up firm two or three times after adjusting, then recheck. On an 80 series the whole system is a bit more sensitive to cable stretch than people expect.

 

[discoverydave]

.

 

[Rdonahe]

Had this same exact issue on a 92 FJ80 I was working on last year. The star adjusters backing off is almost always one of two things — either the adjuster wheel itself is worn enough that it won't hold its position against the return spring load, or there's contamination (dust, a bit of rust, old grease residue) preventing the teeth from seating properly between clicks.

Pull the adjuster out entirely and have a good look at the teeth. If they're rounded off or you can't feel a positive click when you wind it by hand, the adjuster is shot and needs replacing. They're cheap, so if there's any doubt just swap it. Also clean the adjuster threads with a dry brush — never grease the threads, just clean metal. A tiny bit of anti-seize on the threaded rod only, nothing on the wheel teeth or the shoe contact point.

The other thing worth checking is whether the cable itself has any slack in it after adjustment. Even a properly set adjuster will walk back if the cable is stretching slightly under repeated use and the shoes are taking a set. Pull the parking brake lever up firm two or three times after adjusting, then recheck. On an 80 series the whole system is a bit more sensitive to cable stretch than people expect.

Thanks! It certainly could be wear as I have no idea how old the existing adjuster wheel is. I'll get in there again and replace the H/W just for good measure.

 

[synapse]

I got fed up constantly adjusting the rear parking brake, so I built something that can hold a 6000+ lb 80 on 38's doing this: (it's an electronic parking brake)