So today I headed down the interstate about 30 miles away, Jeep drove fine no problems till I got off on the ramp. After I came to a complete stop at the sign it did not want to hardley move even when I had the trottle floored. So I got out and checked the fluid, its still full doesnt smell burnt but the tranny cooler lines were so hot that they brunt my hand. So I let it cool down for about an hour and took it for a drive, worked great and shifted properly. Then we headed back home up the interstate, drove fine all the way home, got out the checked the lines they were hott but no were near as hot.

Any ideas to what could of happened? Could it possibly be a problem with the t-case? Is it a sign that it is getting ready to go? should I replace the tranny, or just add a cooler and new filter and fluid?

any help would be great

96 xj 4.0 with the aw4 trans and np231 t-case

 

Was your engine temp gauge reading high during/after the drive?

 

My best guess would be a solenoid sticking inside the transmission. Solenoids are effected by heat, and a worn solenoid would be likely to fail while warm, but still possibly work while cool. What I suspect happened, was that the transmission was 'stuck' in 4th gear, and the torque converter was slipping, causing it to barely move. Much like what would happen if you unplugged the TCU, and drove it 'manual', but started in drive. The other possible culprit could the the TCU, but I personally doubt that. Familiarize yourself with where the TCU is, and if/when this happens again, unplug it, and try starting in 1/2 gear selector position. If that works, the problem is probably your TCU. If it doesn't, it is most likely a bad solenoid in the transmission. According to fourwheeler.com, [chart] , the fourth gear is engaged when neither solenoid in engaged. So which one is bad? When it isn't working, do the test where you unplug the TCU. If you can get 1st gear, solenoid one is good. If you can't, try third gear, once moving. If that will engage, then solenoid two is good, and you can assume solenoid one. If neither work, there could be a wiring problem, a problem with the TCU, and probably other parts that I'm not familiar with. I would recommend performing this test going down a hill, so you don't heat up your already hot transmission by letting the torque converter slip to absorb all the power. Best of luck, and keep us updated.

 

engine was running at 190, I will try this test next time the tranny does this. Thanks for your help.

 

Ok I found a aw4 out of a 01 xj with only 50k on it for a good price. Now my question is will this one work or do I need one from an older xj like 96,95.94 or what years?