Topic: Tranny not Trany

[enginethatcould]

I have a '93 w/ a 2.5L engine. I recently started having problems with 4th gear. When I shift into 4th I get grinding sound thats pretty loud. Once I get it into 4th it's fine. This dosn't happen with any of the other gears when I shift. I have no knowledge about tranys what so ever. In fact this is my first manuel. Can any one point me in the right direction or place to start?     Thank you!

[oldjeep]

Your syncro is shot.  Only way to fix it is to rebuild the tranny and replace the syncro

[enginethatcould]

Was hoping not to hear the rebuild part. How hard would you say this is?

[oldjeep]

I've only rebuilt T-90's and T-18's before, so hopefully someone else will pipe in.  In general manual transmissions are pretty simple, but in the case of a T18 you need some pretty big bearing pullers to do the job.

[Jeffy]

Seems strange that only 4th syncro's would go bad.  It's usually 1st and 2nd that go bad.

Personally, I wouldn't bother rebuilding it.  You have a 50/50 chance of having problems again.  You'd be better off with a NOS or Salvage.  I'd look into a newer one and swap out the internal slave for a external while I was at it.

[Bounty Hunter]

I would drain the tranny fluid asap, it will likely be full of brass glitter.  Put a good synthetic like Redline MT90 and it may improve, may make it more driveable until you have time for a more permanent fix.

[flyingbrick]

You can put off the rebuild/replace by double-clutching your 3/4 shift.

[jfrabat]

Have you checked the slavecylinder?  I had mine go bad, and I started having the same (or similar) problem in my '94 YJ.  Since I changed the slave (and the whole hydraulic system leading to the clutch) I have no longer any problems.

I would drain the tranny fluid asap, it will likely be full of brass glitter.  Put a good synthetic like Redline MT90 and it may improve, may make it more driveable until you have time for a more permanent fix.

While I did the fix above, I also put MT90 in the tranny, and the shifting is MUUUUCH smoother now than what it was before.  I strongly recommend this!

Felipe

[enginethatcould]

Have you checked the slavecylinder?  I had mine go bad, and I started having the same (or similar) problem in my '94 YJ.  Since I changed the slave (and the whole hydraulic system leading to the clutch) I have no longer any problems.

While I did the fix above, I also put MT90 in the tranny, and the shifting is MUUUUCH smoother now than what it was before.  I strongly recommend this!

Felipe

My slave is bad. It actually leaks a bit now and then. I have the new slave but haven't had the time to change it.

[enginethatcould]

Seems strange that only 4th syncro's would go bad.  It's usually 1st and 2nd that go bad.

Personally, I wouldn't bother rebuilding it.  You have a 50/50 chance of having problems again.  You'd be better off with a NOS or Salvage.  I'd look into a newer one and swap out the internal slave for a external while I was at it.

What other tranny would you recomend? I found an article about fitting an AX15 but I don't know which way to go with it. The cheapest thing would be rebuild kit for about $130 on ebay. I don't want to get stuck with it breaking on me again or costing me more money in the long run.

[jfrabat]

My slave is bad. It actually leaks a bit now and then. I have the new slave but haven't had the time to change it.

My advice; change the slave and mut MT90 in it, and see how it goes before getting into a new tranny...  If the problem persists, then invest in the new tranny or rebuild kit.  By the way, I am assuming that the '93 is an external slave like my '94, but I dont remember if it is or not (dont remember the year they changed it from internal to external).

If it is internal, then I would probably change the tranny, as you will need to take it down anyway...  And that is a real PITA!

Felipe

[enginethatcould]

My advice; change the slave and mut MT90 in it, and see how it goes before getting into a new tranny...  If the problem persists, then invest in the new tranny or rebuild kit.  By the way, I am assuming that the '93 is an external slave like my '94, but I dont remember if it is or not (dont remember the year they changed it from internal to external).

If it is internal, then I would probably change the tranny, as you will need to take it down anyway...  And that is a real PITA!

Felipe

It is an internal.....that's why I have been putting it off for so long. I guess I'll try the MT90 and see if that will hold me over until I get some time to rebuild it or replace it. Haven't decided yet

[Jeffy]

Pre or Post Op?   

[enginethatcould]

Seems strange that only 4th syncro's would go bad.  It's usually 1st and 2nd that go bad.

Personally, I wouldn't bother rebuilding it.  You have a 50/50 chance of having problems again.  You'd be better off with a NOS or Salvage.  I'd look into a newer one and swap out the internal slave for a external while I was at it.

Jeffy,

What transmission would you recomend?

[95yjman]

Before you go and rebuild it, drain the old fluid out and put Redline in it.  It should quiet it down, yes it mask the problem but it is cheaper then rebuilding it.  If it only makes a noise but still goes into 4th just fine maybe try it.  It seemed to work well on my buddies jeep.