i had followed the service manual for my 98 wrangler and had added some 75w 90 GL5 "master craft" to my tranny. I drove it around for about a week and noticed that it wasn't shifting as smooth, had trouble finding 2nd gear, and i could almost feel the metal to metal contact in the shifter.

After posting my conscern on WF CCain had rec. that i use a GL4, seeing how GL4 is whats rec. I guess there is a typo in the service manual all service manuals!

Sweet, so i spent another $50 and picked up 4 qrts of MT-90 75w 90 GL 4

What a difference! Very smooth, effortless shifting, no metal contact feel, and each gear is very easy to get into, down shifting too. I strongly rec.

RedLine MT-90 75w 90 GL4 to be used in you AX-15 tranny

p.s. - save yourself about 1 hr and pick up a cheapo $5 hand pump to get your gear oil into the tranny. After about 2 minutes of squeezing and manuvering with my bottle and some old battery breather tube, i had enough. That little bottle pump made it effortless and quick

Considering trying Redline in my NV3550, as Pennzoil syncromesh has made it shift like complete ass. (I'm not using 1st gear anymore, as going from 1st to 2nd without ultra slow movements causes a nasty gear grind).

you sound like a good candidate