trans problem?? PLEASE HELP

I finally got my car back from the subaru dealer after waiting a good 2 months to have the entire tranny replaced by a factory rebuild. And in the first day of having it back, ive already got problems..

For some reason, after ive been driving a while and slow down from 3rd gear, and then accelerate, the whole car shudders and struggles to get up to speed. This problem is most common through turns; i'll slow down and check the intersection, and as i accelerate, the car shudders and shakes and then struggles to go...
It seems like the car doesnt want to downshift out of the higher gear in order to accelerate. This problem doesnt always happen either, more than half the times i slow down and again accelerate there is no problem.

I took the car into the subaru dealer in the first place because of a shot front differential. I had to get the entire transmission, core and all, replaced after 8 weeks of just trying to replace the one part. So this one really ****s with my head. I cant beleive this...

I heard that the transmission computer adjusts to the driver's style of driving, so im hoping that maybe thats all this is, and after a few days it will disappear. But has anyone else had this problem or does anyone know of a way to fix it???
I really dont want to take it back in; The mechanic i first took the car to couldnt get the job done, and the guy at the subaru dealer turned out to be a real asshole -- so im really screwed if it turns out that this is a serious problem.

I was made truly nervous about the subaru mechanic's knowledge of the car when i got the car back with the abs computer sitting in the backseat. I knew what it was because the other mechanic told me when i went to pick up the car. I sent the car to the subaru dealer with the passenger seat and abs computer out. When i asked him about it he told me that the computer was an "extra transmission computer that the other mechanic left in the car." He then made it sound as if he had done me a favor by putting the passenger seat back in... I drove 50 miles home with the abs light on in the dash, and took out the passenger seat to find no abs computer hooked up. I bolted it back in place and hooked up the wiring harness no problem. I was just gonna let that go until i saw that he charged me 60 dollars to put the passenger seat back in - something i never asked him to do in the first place...

Well im sorry for having this thread be so long, but you can understand that i've had a hell of a time getting this car to run, and i really dont want to have to send it back to another shop. Somebody PLEASE help me..

[Earthworm]

Do you leave the shifter in D? Do you use manual mode?

[gl1674]

This problem is most common through turns

That sounds like an AWD/transfer clutch binding problem.

Are you sure the problem exists when you accelerate in straight line? If it still does, have you checked pressure in the tires recently? Do all the tires match by brand, model and wear?

The transfer clutch binding might be solvable without major repair effort - search this forum for driving in figures eight or ATF friction modifiers.

Originally posted by Earthworm
Do you leave the shifter in D? Do you use manual mode?

the problem doesnt seem to exist in manual mode, but i rarely use it. I only used it a few times to see if the problem did indeed exist when in manual. but I should probly drive around in manual a bit more before saying that it does not. For the most part i drive with the shifter in D

Originally posted by gl1674

Do all the tires match by brand, model and wear?

Actually now that you mention it; a friend pointed out that the rear left was a little flat looking -- i forget to check it myself. Could that be the whole problem?? I'll go check the pressure myself right now.

well i just filled the tires. the rear tire has definately leaked a lot of air since i last checked it. it was running at about 14 psi instead of 29. I was hoping the problem was fixed but on my way home the car shuddered again. Its almost a grinding noise...

it does happen even when i dont turn... but happens most when turning and also i noticed that it seems to happen as i accelerate over hills. There is a four way stop intersection i go through every day on the way home where i turn onto a hill... the car shudders here every time.

on the highway this morning just going in a straight line in stop and go traffic i noticed the problem several times - so im sure its not something that only happens through turns.

is there any way that driving the car home from the mechanic with the rear tire so low could have affected the trans?

I found this in a search:

Originally posted by JDW-SVX

When a fuse is inserted into the "DIFF LOCK" socket, the centre differential (planetary gearset) is locked by the clutch, to provide a permanent 50/50 front/rear torque split.

One side effect of this is that you will get binding in low speed turns, as the centre differential is now incapable of allowing the front and rear axles to spin at different speeds.

Since you have a "DIFF LOCK" fuse socket, you have the VTD system.

this sounds like what is wrong with my car, except i dont have the VTD, i have a fuse socket that says FWD on it, and it's definately empty.

I also noticed that once im accelerated, when i take my foot off the gas, and then just slightly depress the pedal and keep the pedal in the same place -- the rpms go up and down as if i were dancing on the gas pedal. This also only happens sometimes - and the rpms eventually settle. This is barely noticable when it does happen. There are no obvious noises or vibrations in the car; when im really listening for it, it sounds like the car tries accelerate and then shifts up a gear too early causing the rpms to drop, and then shifts back down again allowing the car to accelerate properly for a moment, and then ends up back in the higher gear

[gl1674]

The most common reason for shudder is the binding in the central diff/transfer clutch. But it will only happen in turns. On straight lines all wheels rotate with the same speed and the transfer clutch does not do anything. This is assuming the wheels have the same diameter, of course.

Go ahead and put a fuse into FWD slot. Any fuse will do. This should disable the transfer clutch. Drive with it and see if the shudder is gone.

If it is gone in FWD mode, you will have pinpointed the problem to transfer clutch or it's solenoid.

Another possible reason for shudder would be bad driveshafts, don't know if it is possible to mismount driveshafts to cause shudder - never tried :-)

[oab_au]

Originally posted by gl1674
The most common reason for shudder is the binding in the central diff/transfer clutch. But it will only happen in turns. On straight lines all wheels rotate with the same speed and the transfer clutch does not do anything. This is assuming the wheels have the same diameter, of course.

Go ahead and put a fuse into FWD slot. Any fuse will do. This should disable the transfer clutch. Drive with it and see if the shudder is gone.

If it is gone in FWD mode, you will have pinpointed the problem to transfer clutch or it's solenoid.

Another possible reason for shudder would be bad driveshafts, don't know if it is possible to mismount driveshafts to cause shudder - never tried :-)

Another cause, that you would relate to; could be the timing between the 3 to 2 shift. The high clutch and the band being applied together. As if the high clutch is taking too long to release, when the band applies for 2nd. What do you reckon ?

This would only happen on the 3rd to 2nd shift. If it happend on the 2nd to 3rd shift, it would be the band being too slow to release. Depends which way it does it.

From .the description of the Dealer, they may have done anything to the box.

Harvey.

thanks a lot for all your help. Im not sure if its the transfer clutch; because this problem definately happens when im driving in a line. My rear right tire is leaking, but even after i had just filled it, the problem continued to happen on straightaways...

Still, i'll put in the FWD fuse and see what happens.

whenever i fill my tires, i always put more air in the front than in there rear; there's a plate in the drivers side door frame that says the front needs 33 psi and the rear needs 29; could this difference cause the need for the transfer clutch?

as for what oab_au said... this sounds like it could be the problem moreso than the transfer clutch; because it seems that once i slow down, the car takes too long to downshift. When i accelerate after slowing, the shudder occurs. But if i slow down, and wait a while to accelerate - there's no problem. So maybe when i slow down, the shudder occurs as i accelerate just as it's finally downshifiting. And then because of the acceleration the car needs to then upshift again?? Could that be it?

If that is the case. What can be done to fix the timing? I tried taking it to a different Subaru dealer but the told me i have to take it back to the dealer i originally went to... and i know that the standard dealer action for a busted svx transmission is to just replace the whole thing. Im back in school these days and it will become VERY hard to not only go all the way back to this dealer, but to then get to and from school without the car while the trans is replaced again...

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okay, i just drove around with the FWD fuse in and the problem persits....
i took it back out and noticed that although the car doesnt shudder as i slow down, the trans makes a lot of noise downshifting from 3rd. and only from 3rd.
Maybe i shouldnt describe the shudder as "binding" - im not sure what that means... When i accelerate after slowing, the car shakes - and a loud farting grinding noise comes from the trans. As long as i keep my foot on the gas it stops shaking and then begins to accelerate normally.

could this problem be a result of low trans fluid??

after meeting this mechanic from countryside subaru i wouldnt put it past him to underfill the fluid... or forget to replace the cap...

[Ron Mummert]

What were the original maladies that deemed the tranny replacement in the first place?
Minor note - I doubt the tires have anything to do with the problem, as I had a leaky rear tire scenario for six months many moons ago, & no effect on the tranny, a Suby rebuilt, noted.
What does your warranty have to say about this whole mess?

Ron (Sorry - more questions than answers).

the original problem was a blown front differential.
the "nationwide" warranty i got is apparantly only valid in countryside - which isnt exactly an easy place to get to from where i live. They'll probly just replace the whole trans again, but that means i gotta drive all the way down there and then find a way to get the 20 miles to school every morning

I was hoping to find here the cause of the problem so maybe the whole trans wont have to be replaced and maybe i wont have to go all the way to countryside...

[oab_au]

Hi Simonton,
I am thinking that when they had the trans out, they may have adjusted the band adjusting screw too tight. May be they did not know what the adjuster did, and just tightened it up.

This would cause the band to come on before the high clutch has fully released. This would cause the transmission to bind up ( act like a brake was applied) till the high clutch let go.

I think it would be worth getting the bend adjusted properly, to see if it cured the problem.

All the best.

Harvey.

do you think this is something i could do myself?

I've got the factory service manuals, a torque wrench, and a bunch of socket wrenches. I think i could get under the car... But thats about it. I wouldnt really be able to remove the trans myself... but if this is something i can do without removing the trans please let me know

[Earthworm]

You can adjust the band brake from the top (under the hood) but unless you have a tiny torque wrench you'll never be able to get an exact torque.

The best way to adjust is to make small adjustments until symptoms go away. Obviously if symptoms get worse you're going the wrong way.