Since I put my lift on my 4WD won't engage, it engages at the t-case, high and low range because I can feel it (especially in low range) but even in high range I can fell it in my steering that it is engaged, occasionally the part-time light will blink but lately it does nothing. HOWEVER the front end will not pull, I checked the stupid vacrap on the axle and it is getting plenty of vacuum, and all my lines seem fine. It worked perfectly before my lift, any hints or tips? I really don't want to take apart my axle to investigate. This is a 91 XJ with the NP231 T-case and of course the Dana 30 HP front axle with the vacrap disconnect on it. I have not wheeled it since the lift so I am sure nothing is broken. 
