My '92 YJ 2.5 shifts back and forth from first, second and third just peachy. After that, it's often a task to get it from third to fourth, and sometimes from fourth to fifth. Each of those difficult shifts involves some minor gear crunching and it's often very difficult to get it in the gear selected. Sometimes I have to go from third to fifth, cuz can't get it in fourth. Downshifting from fifth to fourth is much easier (tho it does produce a bit of crunch) and fourth to third is always easy and normal.
The transmission is full of lube, and the jeep has about 132Kmiles on it.
I'm thinking a rebuild kit w/synchros, but figured I'd ask anyway: any chance I can lessen this **** with any particular brand/weight of trans lube, and if so, which kind? I'd rather not rebuild the trans but can if I have to.
Evidence is the Kryptonite of the Pious
I'd drain the fluid and check it out, look for debris, etc. I use regular 10W-30 motor oil in my Jeep standard trans, which is what the dealer recommends too since they altered the formula in gear oil.
Could this be a clutch issue? Just wondering. I have the same issue except a bit more excessive. I can't go into reverse without a nice loud grind. I replaced the clutch, slave and clutch cylinder. I'm pretty sure I bled the heck out of it but still grinds. Will a good lubricant really make a difference?
Desert Rat, reverse is not synchronized. Try this to stop reverse from grinding. Come to a full stop, push the clutch in, shift to second, immediately shift to reverse. That should synchronize your transmission before trying to engage reverse gear.
I had a very similar problem. I was double clutching, repeatedly attempting to get it into 1st (downshifting) and second gear up shifting. I was convinced the transmission was going. Then the clutch master cylinder completely failed. When I replaced it, the problem was gone.
Before you do transmission work, try swapping the clutch master cylinder. Apparently it begins to fail and doesn't completely disengage the clutch. The tiny amount of drag causes the transmission to not synchronize properly.
If you think you're too big to do the little things, you're probably too little to do the big things...