Pops out of gear

[judge]

I have an '83 CJ7 with a 3 speed tranny-(T-150 )-that is not what it had when it left the factory (5 speed), but that is what is in it now. The tranny jumps out of 1st (about 75% of the time) when on "over run"--that is, foot off gas pedal. Just the slightest pressure on the shift lever will keep it in gear. It also "whines" in 1st, but does go into gear easily and I can easily downshift from 2nd into 1st while moving-of course at a reasonably slow speed. So, what should I do first? Not eager to pull the Transmission , but, check shift forks or??

 

[CJ007]

I have an '83 CJ7 with a 3 speed tranny-(T-150 )-that is not what it had when it left the factory (5 speed), but that is what is in it now. The tranny jumps out of 1st (about 75% of the time) when on "over run"--that is, foot off gas pedal. Just the slightest pressure on the shift lever will keep it in gear. It also "whines" in 1st, but does go into gear easily and I can easily downshift from 2nd into 1st while moving-of course at a reasonably slow speed. So, what should I do first? Not eager to pull the Transmission , but, check shift forks or??

Most likely worn synchro.

But, before pulling and replacing/rebuilding, make sure you tranny mount, motor mount or something under there isn't loose as that would cause it to pop out when torque flexes it. Also, look to see if the shift boot or something isn't in the way and its notfully engaging. Then check to make sure fork isn't bent.

If not those, then you can be fairly sure it's the synchros are worn out.