need to know what trany in 1979 cherokee

if you are putting a bigger engine it, you will want to replace the tranny (it is almost 30 years old). so I would get a tranny for the new engine and bolt it in, so you know it is a match

First off, a 1979 Cherokee would have either a 258 inline 6 (4.2 liter) or a 360 V8 (5.9 liter). A 4.8 liter engine was never offered. Secondly, if the transmission is an automatic it will be an AMC TH400, essentially the same thing as a GM TH400 but with an AMC bolt pattern on the bell housing. If it is a manual 3 speed transmission it will have a Borg-Warner T-15. If it is a 4 speed manual transmission it will be a Borg-Warner T-18. A GREAT site to join for all things about Full Size Jeeps is IFSJA.org. Hope this helps.

This WAY too late but I agree with Jonathan. Get a catalog from either Advance Adapters or Novak; they have oodles of information on engine/tranny swaps