I am buying a Chrokee for the t-case and 4.0 and have some questions someone might be able to answer. The guy I'm getting it from has a few of them. One has the part time and full time t-case, the other just has the part time. I assume the part time t-case is the NP231 that I am looking for, but what is the other one. The Jeep with the FT-PT t-case has the one piece passenger side axle that I want to get rid of my CAD. It was also was a police vehicle and supposedly has an upgraded chip in it. I need to know which Jeep to buy...maybe I should just buy both.
What year is the XJ? If it has a V6 it might not work with the YJ. I donno about the spline count inputs, but I know some are different.
XJ Transfer Cases
* 1984-1987 New Process NP207 "Command-Trac", part-time only, 2.61:1 ratio with low range
* 1984-1987 New Process NP228/NP229 "Selec-Trac", full-time/part-time
* 1987-2001 New Process NP231 "Command-Trac", part-time only, 2.72:1 ratio with low range
* 1987-2001 New Process NP242 "Selec-Trac", full-time/part-time, 2.72:1 ratio with low range
I'm looking for the 231...correct? That is the one that I can get an SYE for and maybe upgrade gearing later. I don't know if there are advantages to the other units for a mostly trail use Jeep. The whole reason for finding a new t-case is because the POS NP207 in my Jeep now has no upgrade options.
I have no idea yet what the years are for the Jeeps. I am looking at them this weekend. And they do have the 4.0...it would be kinda hard to build a stroker with my 4.2 crank and a V6.
Yah - your looking for the 231, and it should be bolted to a 4.0L. The only advantage to the Selec-Trac(242) is the full time 4wd for seasonal areas(lots of snow or rain) But with any other mods to the vehicle, it quickly becomes the weakest link.