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Brake drag cause?


NAXJA Forum User
Specs 1994 xj 4.0 ax15
Front axle -1989 dana 30 new calipers pads rotors
Rear axle - 19?? 8.25 with liberty disc conversion new rotors pads one new caliper

So I have been experiencing a slight amount of drag and can't seem to figure out what it is, as stated above most everything is new. Has ss brake lines that have no pinch pionts or kinks. The only thing I haven't changed or check is the proportioning valve, but in my research the liberty swap does not require you to change it. I pulled the front apart the pads are glazed but that is the sxtent of the damage.
Any help would be appreciated this is kinda messing with me
Also the front brakes are the ones mainly affected, with the jeep on stands in neutral I can maybe get one revolution per spin either side with the tire one. The rears feel normal
Replace/adjust your residual valve.
Did you remove the residual valve when you put the rear disk brakes on?

In OEM vehicles, they are present in drum brake systems. For cars with disc and drum brakes, they
would only be used on the drum side of the system
. ... If you had four wheel drums and replacing only one side with disc brakes, the drum side will still need the 10 lbs of pressure. The Residual valve should be removed on the disk brakes.
I've never seen a RPV on any of my XJ's.
OK, define RPV???

Every XJ has a proportioning valve and stock it is set up for drum rears. It is my understanding that they have the residual valve built in for the rear drums, besides balancing the pressure for drums vs disc's. I may be wrong.
Residual pressure valve, and I have WJ/KJ disc's w/ no mods to the proportioning valve.
Ok so where do I find the residual valve and once I do what do I do to it so my brakes will function properly tha ks
You can't find something that's not there!!!
Have you checked to see if the master cylinder is returning back all the way ? some brake boosters have a adjustable rod in side . you can loosen the 2 nuts that hold the master cylinder to the booster about 2 turns and see if the brakes are still dragging .