slips out of reverse

[gonejeepn]

my 89 yj with the ba 10/5 trans slips out of reverse. i have put in new oil (75/90 gear oil) semi syn. does not seem to help. when it warms up its not to bad what else can i do??am i able to put in ATF, like what is in the ax15 trans. any ideas would be great thanks ;D

[diablojeep]

I'm sure you have checked this but I'll ask. How good is the boot around the shifter. If they get old,cold etc they will cause the shifter to pop out of gear. It sounds more like a worn gear or bad shifter fork.