Sm465 swap

You guys are helpful![]()
Will it go into 4th? If not then probably a fork issue. Is it only when wound out? Or will it work if just normal driving?
If it has high miles on it, or has been driven/shifted hard then it could be time for a rebuild. Syncros may be on their way out. Or cracked/bent shift fork. More so if it has an aftermarket shifter with adjustable stops and they weren't set up correctly.
Mine had issues with reverse and I was into it a few times before I finally got it sorted out.