Back in May, I installed a 2.5" Daystar Lift and 265 Nitto Terragrapplers on my 02 V6 KJ. Everything seemed fine until now. It is November here in Wisconsin, and the roads are covered in snow and ice.
Say I am rolling up to a stop sign at 5 to 10 mph. I need to feather the brakes to not skid the front wheels, and maintain my steering ability. I try, but it seems impossible since the rear end is still pushing me forward. The drum brakes don't have enough power to overcome the increased leverage (265 tires) from the road. I push the pedal a bit harder and the front wheels lock up, but the rear is still driving me forward. I panic and throw it in neutral, and all is fine, I come to a nice controlled stop.
Having driven on ice for years, but only in manual transmission vehicles, I never really had this problem. I was able to hit the clutch, and braking worked fine by itself. I like the low RPM torque that the KJ puts to the ground, but its scary when the front wheels are locked up and I can't steer, while the rear is still motoring along with more torque than the drum brakes can apply.
I need to come up with a solution to give the rear brakes some more power, since the rolling torque+driveline torque - brake torque = more than the skid point of the front wheels.
I found a website that explains proportioning valve procedures when installing rear disc on an XJ. I know rear disc needs more pressure to be effective. Is the P-valve any different on the rear drum KJ vs the rear disc KJ? Anyone try it to fix this solution?

Please help! I need some rear brakes so I can steer up front!

Now that I think about it, i had the same problem all summer. At the boat landing, I would have to coast down the ramp in neutral, since in reverse, I would lock up the front tires on the gravel and the rear would continue pulling me down the ramp!

I have ABS so this is not a problem...But if you go to Summit Racing they sell an adjustable valve. I have used them on drag cars and they work great. Just FYI...The ABS works great on the KJs. I live in an area that gets lots of snow every year. But when off roading the valving changes when you drop it down in low range...matter of fact I have never had it go off when in low range even in snow and ice. later...Clint

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before you go the route of a new porportioning valve,do you know if your rear brakes are even engaging.have you had a brake job done on the rear brakes or taken the drum off to see how much pad you have left.sometimes when they do brake jobs they back the drums off with the adjusters to get them out of the grooves and if they havent been adjusted back, then you have little or no rear brake brake.most of the old brake systems adjusted while backing up.make sure every thing is perfect with the old brakes,maybe upgraded the drum shoes with upgrade materials.then if all that is right would i start playing with the balance of the brake system.that will take expirement on a stretch of empty road until you get the precise lockup you want

My rear brakes are fine mechanically. When I pull the parking brake as far as possible, it will hold till over 2500 rpm in first gear. Its the 11%+ more rolling torque applied to the brakes due to the size of the tire that is causing the problem. I need to give 11% more brake pressure back to the rears to overcome the engine torque.

Before I go and buy a new valve, is there anything adjustable on the valve of the KJ?

If i really stomp on the pedal, the rears will lock up, but this is far beyond the point of the fronts locking up, so I no longer have steering.