Originally Posted by NebraskaDizasta
Duh! helps when I actually READ what you wrote.The SYE should not affect your Speedo pickup. I am assuming they are both 242s If it your pickup bolts up the new TC it should work.
I think you mean 231s, the 242 is a part time/full time case used in XJs, ZJs & WJs.
OP, look closely at the '87 T-case. Most '87s came with NP 207 cases.
Here is some info from the FAQs:
The transfer cases used are all chain driven with aluminum housings. NP stands for "New Process" which is the brand, if you will.
NP207 - "Command-Trac" part-time only - 2.61:1 ratio low range - only in 87
NP231 - "Command-Trac" part-time only - 2.72:1 ratio low range - shift pattern 2H - 4H - N - 4L - used '88-'95
Link to FAQ