What is wrong with the trans when it pops out of fifth gear? I had mine pop out a few times now. :'(

 

Judging from your mileage, worn out 5th gear synchro assembly. Since it's 5th, you could probably run it for a long time with a bungee - the hillbilly solution.

 

Scott<br> Wanna could be correct but it could also be the rear counter shaft bearing. I say the rear brg because the front brg will cause it to pop out of low. To check you will have to remove one of the PTO covers and with a pry bar see if the counter shaft moves axialy (back &amp; forth) or raidialy (up &amp; down/side to side) If it does anything but rotate the brg's are NG. <br> These are a fairly simple trans to rebuild you dont need any Getrag only type tools. If it needs brgs give it a try. Nice weekend job. I have all the Timken Brg #'s for this trans so if you do go for it let me know and I will send them to you. You might be able to get the brgs at Auto Zone, I know they have started to carry Timken brgs. or any local bearing house should have them. <br>

 

I appreaciate the replys. Will it hurt anything to run it if it is just the syncros. I have been in this transmission before and I am willing to do what it will take to make it work nice. Its just an issue of finding the time I guess.

 

If it's the synchro you won't hurt anything else, but I'd do the bearing test Winr talked about. I'm not kidding about the bungee, BTW, I've seen it done.

 

Just a general Manual trany tip (especialy applies to Getrags)

Letting your truck idle for long periods of time puts unnesessary wear on the brgs and other internal parts of the trany. The Input and counter shaft brgs are always spinning while the motor is running (unless clutch is disengaged).
I know we like to here them run. but....
Just something to consider