Abrupt Shifting

[Lawsonmh15]

I've been having this prob for awhile. Basically, for the first few downshifts it feels like there is a mismatch in the torque converter leading to one bad shift. This occurs when I punch to pass from 4 to 3. This is an AT. Was so bad on one occassion that I actually heard the tire chirp. Don't think it will get better on it's own. Have checked all elec connections and am now wondering if the Throttle position sensor could have anything to do with it. Also wondering if it could be IACV related. PLEASE HELP!!! Don't want to burn by tax refund on a new tranny. TIA. Oh, the weird thing is that it shifts smooth after 1-3 hard shifts, almost like the ECU finally figured it out. Let me know. Thanks again.

[idosubaru]

Vehicle? Mileage?

has the fluid ever been changed?

does the POWER light blink multiple times when you first start the car?

 

i'd check fluid level and look to have it changed if it never has.

[nipper]

:horse:

Year and mileage and engine type. Otherwise we cant help you at all.

 

nipper

[RallyKeith]

Vehicle? Mileage?

has the fluid ever been changed?

does the POWER light blink multiple times when you first start the car?

 

i'd check fluid level and look to have it changed if it never has.

 

I wouldn't jump to have the fluid changed if it's got high mileage and never been changed.

 

Anyhow, Is this something that is only happening when the trans is still cold? In otherwords, if you drove it very mildly until fully up to temp, would it even do it once? You may just be low on fluid.

 

Keith

[nipper]

Almost everyone here on the list has had the first tranny oil change over 100,000 mils, some like me at 180,000 (previous owner confirmed it was never changed) miles with no problems. The trannies arent like the old trannies where it was pure suicide to change the fluid after 80K.

On any other tranny i would change this opinion (would have to research it ), but here its been proven the sooby trannies hold up to it very well, and usually thank you for it.

 

nipper

[Wayne Boncyk]

I agree totally with nipper. My AT has now seen two complete drain/flush cycles within the past 10K miles, and 4 flushes within the past 50K miles (the result of me trying to clear torque bind with a fluid flush first, then accepting the inevitable and pulling off the extension housing to see what really needed to be done), and it is shifting gloriously better than it has for a long, long time! My mileage: 215K+

 

These transmissions love when you change their fluid -- its as if they have been fully reconditioned, all for only the price a case of ATF! And nipper, my old machine is perfectly happy with its new synthetic fluid -- despite your earlier concerns.

[Lawsonmh15]

Vehicle? Mileage?

has the fluid ever been changed?

does the POWER light blink multiple times when you first start the car?

 

i'd check fluid level and look to have it changed if it never has.

 

99' SUS with 116K miles. Fluid changed, at good level, and I do not get the AT oil Temp light. Not sure about it blinking, but what would that mean? It doesn't stay on. Thanks for your help Gary:)

[Lawsonmh15]

:horse:

Year and mileage and engine type. Otherwise we cant help you at all.

 

nipper

 

Damn nips, I know I've been away for a bit, but sh1t. I don't expect you to remember, but I thought I had that info in my sig.

[Lawsonmh15]

I agree totally with nipper. My AT has now seen two complete drain/flush cycles within the past 10K miles, and 4 flushes within the past 50K miles (the result of me trying to clear torque bind with a fluid flush first, then accepting the inevitable and pulling off the extension housing to see what really needed to be done), and it is shifting gloriously better than it has for a long, long time! My mileage: 215K+

 

These transmissions love when you change their fluid -- its as if they have been fully reconditioned, all for only the price a case of ATF! And nipper, my old machine is perfectly happy with its new synthetic fluid -- despite your earlier concerns.

Real important... Are you FLUSHING or are you DRAINING and refilling. I've only done the latter... Once; like a year ago. TIA.

 

Also, how often do you need to add fluid typically? Not on cars in General (Sub. recommends 50-70K), but you in particular.

[nipper]

Real important... Are you FLUSHING or are you DRAINING and refilling. I've only done the latter... Once; like a year ago. TIA.

 

Also, how often do you need to add fluid typically? Not on cars in General (Sub. recommends 50-70K), but you in particular.

 

I had a shop do a full flush at 180K with the normal auto tranny fluid.

 

nipper

[Lawsonmh15]

I had a shop do a full flush at 180K with the normal auto tranny fluid.

 

nipper

 

Thanks for the reply, looks like I need to take it someplace that will do a flush since JE Subaru South will NOT. I'm always leary of having a "Grease monkey" type of Joint doing ANYTHING other than oil. Anyway, thanks for the info.

[RallyKeith]

 

Anyhow, Is this something that is only happening when the trans is still cold? In otherwords, if you drove it very mildly until fully up to temp, would it even do it once? You may just be low on fluid.

 

Keith

 

Hey, you were nice enough to answer everyone else' questions, how about mine? Seriuosly though, you could have a pump seal/pressure loss issue that clears itself up when it gets warm. I wouldn't expect it on something that new, but it's a thought.

[nipper]

Hey, you were nice enough to answer everyone else' questions, how about mine? Seriuosly though, you could have a pump seal/pressure loss issue that clears itself up when it gets warm. I wouldn't expect it on something that new, but it's a thought.

 

There are two of these threads by differnt people floating around, so i forget who ive said what too. Best case scenario is tired fluid and some gum. Worse case scenario is internal. Usually a weak pump is a tim lag shifting from r to d.

 

nipper

[Lawsonmh15]

Hey, you were nice enough to answer everyone else' questions, how about mine? Seriuosly though, you could have a pump seal/pressure loss issue that clears itself up when it gets warm. I wouldn't expect it on something that new, but it's a thought.

 

I've tried all that I can think of and no matter how it's babied, it always does it at least ONCE. I checked the level today and saw fluid out to full hot. I remember reading something about bubbles, I had a few tiny bubbles in the marking holes. Don't know if this means it is low, thin, normal or otherwise.

 

The weird thing was that after pulling the dipstick and wiping clean, black streaks were left on the paper towel. Wipe it clean (no streaks) re-insert, pull, black streaks on what looks like otherwise clean fluid.

[Lawsonmh15]

There are two of these threads by differnt people floating around, so i forget who ive said what too. Best case scenario is tired fluid and some gum. Worse case scenario is internal. Usually a weak pump is a tim lag shifting from r to d.

 

nipper

 

What type of lag are you referring to. I keep my foot on the break until I feel it go into gear. Do you mean it just takes longer to engage, or do you feel it grab and jerk or what? Thanks for the help.

[nipper]

Its a throttle lag. Nothing happens when you stomp on the gas peddle at first from a dead stop, not even a crawl. There is nothing wrong with the transmission. i'm going to assume that the fuel pump or pressure regulator are getting tired. At the next service ill have my mechanic look at it, or if i can find pump thats afordable change that myself.

 

 

nipper