Trying to get the most out of my AX5 tranny on my 94 yj. This is my second jeep that I just traded a motorcycle for. Jeep is in good shape but needed a good cleaning. I think the synchros are going bad and want try a good synth tranny fluid before rebuilding the tranny. What do you guys and gals think. Royal purple or redline mt 90. The redline is hard to find on the shelf.