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Trans / clutch intermittent shifting problem


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Ok, I can't figure this out.   2002 Legacy Outback with a 5mt.

 

This whole problem came about because my front differential was bad.  I got a 5mt from an 02 Forester and swapped it in.  New pressure plate, clutch, and flywheel, as well as throwout bearing and trans input guide bearing.  I figured with a lower first gear and higher 5th gear, it would be nice; and it was for the first few weeks.  Then all the sudden I started having issues getting it into gear, but only sometimes.  

 

Let me try and describe it.  Occasionally, and uncorrelated to temperature (of the car or surroundings), humidity, time of day, phase of the moon, and whatnot, it will not go into 1st or 2nd without massive grinding.  So I don't try when it does this and instead pop it into 3rd, get it rolling fast enough that the trans speed matches the gear speed, and go into first.  For whatever reason, it'll go into 3rd at these times, but usually not 1st or 2nd.  It's almost as if the clutch doesn't disengage enough to allow it into gear.  That would make sense if it happened all the time, but it doesn't.  Sometimes it'll shift just fine, with no issues at all.  Other times it has this difficulty getting into gear.  When it does have difficulty getting into gear, there's massive clutch chatter, as if the clutch is misaligned.  

 

When I have this difficulty getting into gear, I can hear an RPM-dependent whining.  I don't know if it's the clutch disc slightly dragging between the flywheel and pressure plate, the throwout bearing on the pressure plate, or perhaps the guide bearing in the flywheel.

 

I bought a new slave cylinder and hose, but haven't put it on yet; my wife is out of town and I have no way to bleed it otherwise.  I bought it thinking that just maybe the old slave cylinder isn't disengaging the clutch enough.

 

I was also thinking perhaps the guide bearing is pressed in too far and the input shaft slips out.  That might explain the massive clutch chatter and occasional lack of problem (like when it's actually aligned).

 

I really have no idea, and before I pull the trans again, I'd like to get other opinions.  Has anyone had an issue like this?  Any thoughts?

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Pilot bearing can't be pressed too far....it stops on the crank.

 

Could well be the slave cylinder.....

 

or it could be the clutch fork bendding/breaking......for 30 bucks I replace them when I do a clutch anymore......seen 3 broken forks this year already.

 

Also could be one of the PP bolts backed out or broke....allowing one side of the PP to lift when depressing clutch.

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try blipping the throttle in neutral after lifting the clutch pedal - immediately push it back down and complet the shift from 1 to 2 .(double clutching)

 

could be the synchronizers are damaged, also, what kind of gear oil did you use? many people report problems with synthetics.

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Thanks for the replies, and here's a slight update:

 

I replaced the slave cylinder and hose, flushed the old dot 3 fluid out, filled it with fresh dot 3, and bled it.  It helped, but didn't eliminate the problem.  It still has intermittent issues going into 1st and 2nd, but it'll now at least go into gear without grinding, so that's a plus.  

 

The intermittent clutch chatter remains, and as before, if it's difficult to get into 1st or 2nd, clutch chatter ensues.  Double clutching doesn't help.  Rev matching does, but unfortunately I can't rev match when stopped unless I turn off the car :)  I did use synthetic - Mobil 1 75W90 IIRC.  It doesn't seem like a synchro issue as it's intermittent.  Although I'm not positive, every other car I've had with synchro issues had the problem all the time, not intermittently.

 

So maybe I missed a bolt when tightening the pressure plate?  Or maybe the input shaft isn't seating in the pilot bearing?  It looks as if the trans will be coming out again, I'm running out of ideas...

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So you swapped trans'. Did the donot trans have the same final gear? did you swap a matching rear diff? suppose you have a discrepancy in final gear between the donor trans and the existing rear diff.

 

and my car drives similar to what you describe, full time rx trans with different size wheels between the front and rear axles, causing a slight rotational difference across the center diff, making the gears sticky, and downshifts almost impossible.

Edited by MilesFox
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you may indeed have multiple problems - subarus have had issue with clutch 'judder' in the past - even TSBs on that issue.

 

 

try a non-synth GL-5 fluid. easier than disassembling something.

 

but, fluids will certainly not repair broken metal. it's just that, the soob manual trannies are odd, you need a fluid that plays well with a differential AND a transmission. synthetic oils don't let the synchros spin enough.

Edited by 1 Lucky Texan
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Clutch chatter is probably due to one side of the pressure plate not fully releasing. This can happen if the quill that the TOB slides on is worn unevenly because it will cause the TOB to cock off to one side as it moves toward the pressure plate. It will also cause the TOB to drag as it releases and/or not fully release right away.

Maybe this could cause a whining/whirring sound if the TOB is still rubbing on the pressure plate fingers?

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Well ok, I spoke too soon.  The problem is back in full force; maybe it just felt like being nice after I replaced the slave cylinder.  When it won't go into 1st or 2nd at a stop, if I double clutch very fast, I can get it into 2nd with a slight pop.

 

02 Forester and 02 Outback both have 4.11 final drives, so I'm good there.  I agree about the oil and synchros vs final drives, although I'm guessing that won't do it.  I may give it a shot though.  Also, the new clutch came with some info about a repair sleeve or some such thing - could that be the issue?  Perhaps the TO bearing is actually going crooked because the thing isn't sliding evenly...

 

I'll probably start pulling the trans tonight.  Fun fun.  I'll report back with whatever I find.

Edited by Romy
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Did you install the repair sleeve that came with the kit?

If not, that's your problem.

The repair sleeves require a larger inside diameter release bearing. Installing the larger bearing without the sleeve will allow the bearing to go WAY sideways.

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That's the ridiculous thing about the kit - it had those instructions, but there was no sleeve included.  The TO bearing fit just fine without it.  I'll be pulling it tonight anyhow.

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If the kit came with those instructions it was probably supplied with the sleeve and matching TOB. If the parts were not shrink wrapped or bagged together, its possible someone bought that kit and returned it, or someone at the store removed the sleeve from the kit.

 

The sleeves are not very thick, so the difference in diameter is fairly minor, but that small difference makes a big difference when it comes to properly releasing the clutch.

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Yep, I think you're right.  I emailed rockauto about it; I doubt they'll cover it but at least they should know.  That was dumb on me for not realizing if the instructions were there, it probably meant the sleeve should have been there too.  And if it was a return, that's dumb on rockauto for not confirming the box contents before reshipping.

 

Once I get it apart I'll inspect the damage.  I'm hopeful that the PP and clutch disc are ok, but not counting on it.  TO bearings are relatively cheap, and as long as the trans quill is ok, I'll just plop a standard one in there.

 

Thanks for the help; I'll report back when there's news.

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Rockauto is pretty good about returns, especially with wrong or missing parts, but they would probably want the entire clutch kit returned (possibly how/why you ended up in this perdicament).

Inspect the clutch disc and pressure plate carefully. If you see hot spots (multi-colored discoloration) or glazing, don't re-use them. Also check the fingers on the pressure plate for grooving/scoring from the TOB.

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  • 2 years later...

I am wondering if I am having a similar issue. :blink:

 

I recently had to replace the TO bearing on my '03 Baja. The old one had finally seized and was chewed up significantly. I purchased a new clutch kit from Napa Auto Parts, and it didn't mention anything about a sleeve in the kit, nor did it include one. The new bearing seemed to be a snug fit.

 

Recently (as within the past few days, though I replaced the clutch weeks ago), I found that I could not shift into 5th gear, and occasionally could not shift into 3rd, either. If I pulled over and turned off the car, then I could work the shift lever through all the gears. I then started driving again, and had use of all gears. Stopped again at another destination, started driving again, and again I could not get into 5th, until about the third time after downshifting back into 4th gear.

 

It feels like a synchromesh problem, since it feels like it's trying to grind if I try to shift. I do notice, however, that the engine RPMs definitely drop, so I assume the clutch is doing its job and disengaging the engine from the transmission. This NEVER happened prior to the TO bearing and clutch replacement. I'd really hate to have to rip this thing out again...

 

If it a synchromesh problem, does anyone know of a source for these parts, or is it more advisable just to swap out the gearbox? While I have not done a great deal of research yet, they seem rather pricey, considering...

 

Any ideas you can give me on this subject are welcome and appreciated!! :D

Edited by BajaMikey
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Well, last night it happened again. Went on the freeway, could not get into 5th. Exited, and could not downshift into 3rd (initially), but when I slowed down to 35 I suddenly got 3rd, and had 5th as well. No noises or problems the remainder of the trip to my destination.

 

I may have a better idea of what's going on, though. As I sat in the parking lot, I was moving the shift lever through the gears (engine off). I noticed during this time that I would hear/feel a thump in the shift area whenever I went into 2nd or 4th. :o

 

I'm now suspecting something wrong with the shift linkage or thereabouts, which is binding and not allowing it to move into the upper area (1st, 3rd, 5th). As I left to go home, I did not have these gears available. I had to drive it home using only 2nd and 4th gear.

 

I really hope this is a simple thing to fix.... :wacko:

Edited by BajaMikey
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Check the little u-joint on the linkage where it hooks to the transmission. Mine was making me berserk with pretty much the same symptoms, and I found the bushings were shot in that joint. With just that little bit of slop, it was hitting two shift rails at the same time, and the interlock was stopping it. Even though I was pulling it to the sides as far as it would go. One of the pivots in that joint is "non-servicable," it has a pin through it which is peened like a rivet. I just ground the peened part off, and then drilled and tapped a small hole in the end of the pin for a 1/4-20 screw to hold it in. I used pieces of nylon tubing for replacement bushings. Shifts perfectly now, and I had to take back all the swear words I called the clutch  :D

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I never followed up with this thread. It turned out the TO bearing didn't fit as snugly as I thought it had. The sleeve was indeed missing causing the pressure plate to not release evenly. I ended up just getting a new TO bearing that was not meant for a sleeve and it was all ok after.

 

Your problem reminds me of another problem I had with a VW bus. I was on a long trip in the bus and an odd semi rubbing/grinding noise began to develop. The trans also started getting louder just while in gear. I probably drove about 3000 miles on it before I was in a location to pull the engine out. When I did pull it, I found that the pilot bearing had disintegrated. Easy enough to replace. However, the damage had been done at that point and had I been more astute at the time I would have realized the trans input shaft leak was probably an indication of what was to come.

 

Initially, shifting into only 1st and 2nd, it seemed good to go. But as soon as I got on the highway I found 3rd and 4th were near impossible to into. After I got the bus home and pulled/opened the trans, it turns out that the unsupported input shaft had worn the internal bearings on the main shaft out. It happened slowly over time I suppose so the shift forks wore to match. Realigning the input and mainshaft (which are basically the same shaft) caused all the formed wear patterns to now be misaligned. And so there went 3rd and 4th (1st and 2nd were engaged on the secondary shaft).

 

I don't know if this is your problem or not but the Subaru and Bus transaxle are extremely similar. As others have mentioned you could check your shifter linkage bushings. There are two replaceable ones and a third that can be fixed, as mentioned, by resleeving with some hard rubber or nylon after drilling the old bushing out. But it does seem suspicious that the bushings would be bad when your TO bearing was toast...

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