88 4runner, stock saggy rear springs.
when braking, even on dry pavement the rear brakes will lock up leaving no traction and sometimes an inch or two from having to explain to the driver in front of me why he needs some new body work <img src="/forums/images/graemlins/lol.gif" alt="" /> on wet pavement it's incredibly worse! It feels like the front brakes don't even work. It's been getting worse lately and need to know what to check... I know there's some sort of pressure valve in the rear of the runner but how to fix the brakes is beyond me....
HELP - PLEASE <img src="/forums/images/graemlins/shiner.gif" alt="" />
AUSSiE

check for leaking axle seals (gear oil on the brake shoes). yes, oil makes brakes LOCK UP, not slide.

so what your saying is that oil on the brake shoes will help the brakes lock up? That sounds a little weird, but I believe you. Nothing was leaking when I checked the rear brakes after I bought it last January but I guess things can change. I'll check on the weekend for leaking axle seals, but i'm thinking it has to do with that brake valve in the rear - LSPV I think it's called. Thanx for the suggest though.
AUSSiE

I was having the same sort of problem last year. I had been doing lots of wheelin in the rain, going through large puddles and such. Changed the rear brake pads and all was good. <img src="/forums/images/graemlins/kewl.gif" alt="" />

<img src="/forums/images/graemlins/patriot.gif" alt="" />

The LSPV adjusts the rear brake bias, the lower the rear end sits, the more "load" the LSPV thinks is on the rear axle so the more brake pressure it gets. Might try adjusting the LSPV sensing rod so that it is not so high on the valve itself:
- http://www.4crawler.com/4x4/4R_suspension.shtml#ProportioningValve

well I never thought of running the truck through water to wreck the brakes.... to think of it that's about when the brake problem got worse! Maybe a little R&R of the brake pads would be a good idea now anyway. Modifying the LSPV sounds like a good idea too - ohhh.... and maybe staying out of the giant puddles of water that call for me as well <img src="/forums/images/graemlins/smile.gif" alt="" />
Thanks alot everyone - i'll definately check those brake pads on the weekend and keep all posted.
AUSSiE

If you've gotten oil on the brake shoes it tends to burn in, making them sticky and quite prone to locking. Replacement is necessary, and you need to very thoroughly clean the metal drum as well.

The load sensing proportioning valve (LSVP) is on the right frame rail, and is connected to the rear axle with a rod. When working correctly, it balances the rear braking to the load in the bed. If your truck is lifted and it wasn't adjusted, you can have problems with lack of rear braking. Typically they don't go out of adjustment.

However, LSVP's do get gunked up and quit working, prematurely locking up the rear wheels. Removal, disassembly and cleaning restores them to full functionality.