Manual transmission is going to need a rebuild eventually. What do I do?

Every gear is annoying to shift into, mostly 1st, 2nd, and especially reverse. While driving you have to carefully guide it into gear sometimes. It's been like this since I bought it 20,000 miles ago. The odometer reads 535,000 miles and the mileage on the trans is unknown...

I thought replacing my shifter bushing and clutch fluid would fix it but was not impressed with the test drive and now I think it's the clutch forks.

I'm not afraid to rip apart the transmission if needed. I've rebuilt one before but I would rather only need to do it out of necessity since I need this ride for work and school.

Since this problem has been going on for a while, I think I have a lot of time but it will get worse of course. My plan is to find a replacement transmission, rebuild if needed, and swap it into my truck. (probably in the spring)

 

How's the clutch feel? Does it grab/engage at what feels like a normal spot? Does it engage down by floor?

Just wondering about a possible clutch issue that may not be fully releasing the disc

That is a crap-ton of miles on those syncros tho..

 

there should be a date code stamped on the housing underneath...if you are curious if that transmission is original to the truck and not priorly replaced?

this is the R150F?

 

I "rebuilt" an R150F a couple years ago. It's vastly simpler to rebuilding an auto. I rebuilt a 4L60E out of a chevy about a decade ago and that was a beast for a first timer.

Amayama and partsouq, and Marlins upgrades are great sources. I had to replace the input shaft due to pilot bearing wear. The no deminimus thing right now makes amayama and partsouq problematic though.

You have so many miles i would source a lower mileage unit and rebuild that. Take special attention to 1st gear as they like to pop out a lot and the difference between a transmission that rarely pops out and one that does frequently is not a lot.