I have a 2000 ranger with a manual transmission and all of a sudden it won't go into 4th gear. All other gears are fine. Does anyone know what may cause this and what the fix for it is?
Do you hear any funny noises? (might be faint, listen closely)
If all the other gears are just fine and its only one gear, that could point to an extremely worn or broken synchro.
Try shifting it to 4th gear when engine is off. If it shifted smoothly with engine off, I would go with damaged synchro. I have a buddy who rebuilt manual transmission, but he is in Fresno, CA.