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Guest jcniest

Strange AT shifting...

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Guest jcniest

I have a strange AT shifting situation on my 1991 Legacy. When it's driven from a cold start (meaning the AT oil is cold), the tranny shifts smoothly as normal. However, after being driven for awhile (or when the AT oil gets hot), when shifting up, the tranny doesn't shift gear (1st to 2nd usually) until the RPM reaches 3500-4000. That's too high, I think. As far as I can remember, it never did that before until this year.

 

I have synthetic blend tranny fluid in the tranny.

 

Anybody has this problem before? As always, thanks in advance.

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Guest Legacy777

What type of throttle input are you giving when it won't upshift until revs are high?

 

Two things it could be are improperly adjusted brake band, and or the tranny has learned some weird shifting habits. You can reset the TCU and see if that changes anything. If not, it's probably the brake band.

 

To reset the TCU pull fuse 16 (EGI/TCU) for 10 min.

 

Here's some scans from the FSM on the brake band stuff

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/transbrakeband.jpg

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/transbrakebandadj.jpg

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Guest jcniest5

Just normal acceleration, pressing on the gas pedal. Sometimes I do it a little hard cuz it doesn't seem to have the lift it used to anymore. It happens both when accelerating from a near stop, such as at a Yield sign and/or from zero up.

 

Could it be that my AT fluid is too much? I'm still confused

on how to measure the fluid. Should the engine be running or off when measuring the AT fluid? I found that when the engine is running, the fluid is between Hot and Cold. If the engine is off, it is way above Hot. So, I'm very confused.

 

I will try resetting the TCU first, then see what happens.

 

Thanks much!

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Guest bill rigsby

Our 95 Impreza has a similar shift pattern,

can this year TCU also be reset in a similar manner?

 

 

Bill

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Guest Legacy777

Bill,

 

Not sure if yours can be reset the same way. Is your car OBD1 or OBD2? If it's OBD1, then yes, but the fuse may not be the same fuse number.

 

 

To check the trans fluid. Drive the car around, for a few miles, get the transmission temp up to normal, but not too hot. Park on a level surface. Move gear selector into park. From there, slowly cylce through every gear from Park to 1st, and then back up to park. Leave the car running, pull the dipstick out, wipe it and recheck the level. It should be between the upper H & L marks. It may be a little difficult to read, but you should be able to get the idea.

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