brake diagnosis help

[darkshadow]

ok, on my 88 3/4 tom 4x4 sub i had the bracks done about a year ago when i put it back on the road.


new front pads a new rear line, drum, wheel cyls, shoes and springs.

in the summer i replaced the pads and calipers do to them starting to sieze.


now i have noticed that my front brakes are locking up because my rears seam to do nothing. I have been thinking that this might be my proportioning valve.

i havent had the time to look at the system much due to my new job, but the cyls done seem to be leaking. could it be anything elce?

 

[k20]

start w/ the easy stuff, check the rear brake adjustment, and just an aside, dont be a moron like me, and try to adjust em w/ the ebrake on (not thinkin about it), they wont adjust.

 

[darkshadow]

yeah dident think of it.

its bad not i wont let the wife drive it when its snowy because the fronts will just lock up and the rears ant doing nothing, i could learn alot by tearing into them but time time time, i will try to ajust them soon.


any other ideas?


and if it is the propotioning vales lets say. could i put and ajustable one in in place of it in case i want disks in the rear some day? ( well i want them but IF i ever do them)

 

[k20]

not sure on the prop valve, but I believe the stock one holds residual pressure on either front or rear, you would have to find a way to keep that with the adjustable one. Also, not sure if you have a height sensing valve on the back of yours or not, but if you do, its possible its screwed up.

 

[darkshadow]

ah i did but it was remove (suposidly) properly and bypased, right befor i got the truck a few years ago. i am sure it was done right as the guy dident skimp to get it saftyed so i would buy it

 

[dyeager535]

I wouldn't blame the prop valve.

Make sure the rears are adjusted right, and figure out how the height sensing valve was "fixed". If it was just locked in one position, you can get either too much or too little braking from the rears.

 

[k20]

since its been 'fixed' has it always had weak rears or has it gotten gradually worse? If its slowly gotten worse, bingo, adjust the rears and ill bet that will fix the problem.