Driving back from Atlanta on Sunday I discovered that someone stole 5th gear. 1-2-3-4-???-6 and reverse work fine. There isn't even a notch for 5th anymore. I've tried engine off clutch in or out, Engine on matched revs, double clutch, 4-5, 4-N-5, 6-5 or 6-N-5, engine warm or cold and verified that no carpet is bunched up under the clutch. It's as if I never had a 5th gear.

Dave was it the TSB, 5th gear synchros or something else?

Based on this thread, I'll check the TSB and replace some fluids (it's time for the 36,000 mile service anyway).

https://www.s2ki.com/forums/showthread.php?...25&pagenumber=1

 

I had the same exact problem, I found that it was worsened by grinding gears. It was hugely improved with a fluid change as well. I was able to get it working again by doing something I don't recommend: forcing it. Then it was hard to get it out of gear once it got in. I had to kind of give it a quick hit (towards 6th) to get it to loosen up and eventually I got it out again. The more I took it in an out of gear the smoother it got. If I didn't grind anything for a couple weeks it seems to go away. Witht he fluid change it was way better and I haven't had the problem since.

Chris

 

Well I tried TSB046 myself and replaced the transmission fluid but still no fifth gear. Although that original silkiness is back for the gears that remain. I tried forcing it as much as I felt comfortable with but still no 5th gear.

I haven't checked the clutch fluid, but since 5th gear doesn't work even with the car turned off and not moving, I don't think that will have any effect.

One note, that little nylon bugger on the end of the shifter is a pain in the a$$. I cracked it trying to pop it off so that I could clean and lube it. I had to order a new one ($2.50) and cracked the new one trying to put it on. I guess I'll be ordering another one. This time I'll try warming it up a bit before installing it.

 

The problem comes down to this...

5th and 6th gear share a synchro sleeve. This sleeve is slid one way to engage 5th gear and its slid the other way to engage 6th. The sleeve is a cylinder with splines along the inside that has both the 5th and 6th gear synchros riding inside of it locked to those splines. As the sleeve is slid over the synchros to engage a gear the splines at the outer edge of the cylinder inside the sleeve engage the gear being selected. When you hear a gear grind its these splines that are hitting the gear being selected. If you grind the gear enough you will end up damaging the outer edge of the sleeve that's used to engage 6th gear. Oddly enough this doesn't seem to prevent you from continuing to select 6th gear. But, the damage is sufficient enough to keep the sleeve from sliding in the other direction when you go to select 5th gear.


In my case I lost 6th gear. This is because i often missed the 2nd to 3rd gear upshift by selecting 5th instead of 3rd. Tho I didn't always hear a gear grind it occurred enough and eventually resulted in enough damage to the Synchro sleeve that 6th gear became unselectable.

In your case, my guess is that you take a highway to work every day and when you get on this highway you bypass your shift to 5th gear and go directly into 6th. But, you make this shift at the same pace as you make the other shifts. Unfortunately, this doesn't leave enough time for the synchros to do there work because the gear speed differential the synchros have to overcome is much greater when you skip a gear.

Things become much clearer when you hold the affected parts in your hand to see how they work.

 

Hmmmmm! That makes some sense. I promised myself after I lost 5th that I would make sure to use it (or at least double clutch) when I got it back. I did notice from the transmission drawings that 5th and 6th were at opposite ends of a shaft. I guess that would leave the synchro teeth permanently out of alignment with 5th gear.

Any ideas for reforming the synchro without disassembling the transmission?

 

cjb80 did the only thing i can think of that might work. I say "might" because you are more likely to bend a shift fork than accomplish a fix. A fix in this case means clearing the burrs that form at the edge of the sleeve from repeated grinds.

And to clarify, Its not the brass synchro rings that are damaged its the steel Synchro sleeve that is damaged.

 

Fixed - A couple of quick hard hits (by the mechanic) and 5th gear has returned. I was to worried about breaking something so I never used enough force. Thanks for the diagnosis - invaluable info. No more skipping 5th gear.

 

Dave,


Have you found anybody who makes steel synchro's for our tranny??????

 

I wasnt looking. Besides, its not the brass synchro rings causing the problem its my bad shifting technique and the resulting steel on steel damage. I am however curious about the new carbon synchros installed in the '04 tranny. If they operate quicker than the brass synchros than that may help alliviate some of the damage.

 

I'll have to dump my transmission fluid to see if I've got any burrs. On the feeble attempts I tried to force 5th, it took a lot of force to return to neutral at which point, I had to force it into another gear to get it out of neutral. Everything is a little notchier than I remember, but improving with use.


After performing the TSB-046 myself (simple but frustrating) it seems like there are several possible causes for shifting issues.

Covered in TSB-046 (Which does not really point these out)
1. Little nylon bushing (pivot cover) at bottom of shift lever breaks off and jams between shift rod and tranny case.

2. The nylon sleeve and/or pivot cover on the shift lever is sticking preventing the push down to get reverse or the pop up back to forward.

3. The shifter portion of the transmission is not properly aligned where it bolts to the console preventing full movement of the shift lever.

Shifter Sleeve-
1. The teeth in the steel synchro-sleeve develop burs due to grinding during shifts, or stress from skipping an entire gear before the synchros have synchronized during shifts.