when ever i drive long distances on the highway after an hour or so my gear pops out. i put it back in and it'll do it again later, synchros?

 

Detent ball or spring. Internal to the transmission. Try changing the fluid first, and adjusting the shifter cables- it just may work. If not, you're only out a few bucks, and you'll have to take your trans to someone who knows what they're doing to get it fixed, or just buy a salvage yard trans for ~400 bucks. Probably cheaper than getting your detent fixed.

 

i've already changed the fluid and i have another tranny already bought it from the junk for $150 with 86k on it. i just need this tranny to last me through winter.