overdrives

I tried the search feature but, couldn't find what I was looking for. I've got a.....58 to 61 cj5. Not sure exactly. She's stock with an f-head, t-90 and a model 18 t-case. Rear dana 44 (tapered) and a dana 27 front with, I'm guessing 5:38's. I love this little jeep, it's number 5 for me. Anyhow, I'm considering an overdrive for it. I don't want to modify it much if any at all. Could I get some opinions from some of you jeep guru's? Thank's.

 

Absolutely cannot live without mine.I have a 62 CJ5 w/ V6 conversion.
List your seriel number and someone here will tell you the year. There are two different tooth counts and that's all that counts unless you have an original V6 which isn't possible for the years you stated. One is 26 and one is 29. Take the cover off the transfer case and count the teeth on the gear inside. Lift rear wheels a little just in case the T case is overfilled w/ oil.
The tooth count is needed when you go to order one, Bill

 

You need the spline count as well (6 or 10).

 

Love mine!