Hello. Can anyone give me some insight on the rear brakes of my truck. Rear ABS only. High pedal. Rear grabbing upon a rolling stop. Winter time in snow, complete lock up at any speed. No rear ABS at all. Drums turned, new shoes, new hardware and wheel cyl a year ago. No rear dif lube leaks. Took apart rear last week. Took shoes off and pins blew out of wheel cyl. Needed to bleed rear. No ABS or brake lights on. Proportioning valve pin pops out on end when brakes applied. Is the RWAL or SWAL bad? Proportioning valve bad? Bad Master cylinder? Can't get the RWAL or SWAL valve anymore. Unpluged the connector from the RWAL and no change. Just got the ABS light on. Does it in 4 wheel drive or 2. Doesn't matter. Please help. Thanks, JIM

 

I would lean toward one of the three components in eng bay. Prop valve, Mast Cyl, or booster in that order. Rear breaks only react with action of these three parts. Only other thing may be emergency break adjustment, but you sound like you know what your doing so I would not consider that.

 

Thank you for the reply. Yeah, I checked that also as you assumed. They are adjusted properly. I don't want to replace all the hydraulic components, you know? I can't get the RWAL valve anywhere. Any testing or can I take the valve apart to clean? Is there a bleeding procedure if I do so? Thanks again. JIM

 

well if the ABS isnt working, then when you hit the brakes they will lock right up. since you replaced all those parts, its probably an excellent brake.

I just did all my brake, and my brakes will lock up if the pedal goes more than a 1/3 way down.....so id say just replace the ABS sensor and see what happens