It can be done without removing the trans from the vehicle. Remove the t-case, remove the rear trans mount if you didn't have to removing the t-case, unhook the speed sensor and remove the bolts that hold the overdrive unit to the back of the transmission. The unit can be popped off after that, you will lose a ton of fluid and where the shaft comes out of the transmission there will be a round aluminum plate with a spacer and a bearing, don't loose those as there are the thrust surface for the aluminum plate (which is the overdrive apply piston). The tricky thing putting it back on is lining up the park rod which goes into the back of the OD unit. Make sure the transmission is supported when you take the crossmember off.....Not a bad job, time consuming though.
What is the problem with yours?
Dodge/Chrysler/Jeep Technician 14 Years
ASE Master Certified
L1 Advanced Engine Performance