# Hard Shifts after driving at speed



## Goat51 (Oct 27, 2015)

Hello - I didn't see this problem posted yet. I have a 2005 A4, all stock but CAI and mufflers. It has 43,xxx miles.I've owned it since Aug 2015. Last year I didn't have this problem and it has now occurred twice, consecutively. 

Driving at normal highway speeds, up to 90mph for 30-60 minutes, then I pulled off the freeway, hit a few stop signs to putter around in a local town, the car shifts fine.

Last week and this week, I was on a few speed runs. We drove 100mph for a while, say 10-20 minutes, then hit 140. Got off the freeway and once we stopped at a stop sign (was in 1st) the shift from 1st to 2nd, then 2nd to 3rd was hammered, a real slam. And a few times there was a delay, half second, before it shifted and the shift was again slam. (this was at normal driving speeds, say up to 40mph). I then stopped for some food, the car sat for 40 minutes and when we started to drive, the shifting was "normal". We didn't do anymore high speed runs, normal freeway speeds.

Just today, we did the same speed runs, 100mph+ and topped out at 147mph (fastest yet). We were driving at these speeds for about 20 minutes. When we pulled off the freeway, again, really hard slams for shifts at normal speed (1 to 2, 2 to 3, 3 to 4 - up to 45mph). We stopped for food and turning the car back on, it shifted fine all the way home. Going home never exceeded 90mph.

My thoughts are heat or the ECU is getting confused: the stop cools the fluid or the stop/restart resets the ECU. The tranny fluid is full, no other issues.

Any ideas?
TIA - Goat51..

ps. anyone know a good motor/tranny shop in Minneapolis/St.Paul, MN?


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## svede1212 (Nov 1, 2005)

Sounds like a heat issue vs the computer. It may be the trans valving is sticking. You could try putting a trans cooler on and if that doesn't resolve it it may be time to take it to a tranny shop.


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## Goat51 (Oct 27, 2015)

thanks Svede. I used BG44k for a fuel cleaner, are you aware of this product? We used their Fuel Injector cleaning system in the shop I used to own. I think I'm going to try their ATC Plus, AutoTrans conditioner. (I didn't even think of it until you mentioned it, so big thanks!) It kills me that the tranny could be going at only 43k miles. 

Some guy on another thread said he uses CASE transmission fluid instead of standard ATF. He said since it's for tractors, it has a higher boil point. Have you heard of this and have any knowledge you could share?

I've started to go to local car shows and after talking with the Corvette guys, because I've only see one GTO/our year, I have yet to get the name of a good mechanic for motor or trans work. A few folks mentioned TSI for tranny work.

Finally, (I haven't educated myself of trannys), If I do go for a tranny rebuild, from your experience, what parts should I buy that are more robust, heavier duty, to enable the tranny to functional longer with the heavy downshifting I do?

I appreciate your help and guidance tremendously.
Goat51


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## svede1212 (Nov 1, 2005)

Some vendors like Tick and RPM offer upgraded transmissions. From your join date it looks like you might not be the original owner. As with any used car it's hard to know what it's been through. There was a guy that upgraded everything like axles, drive shaft, cam, headers, heads, supercharger, etc. and then when his lease was up put it all back to stock. The next guy got a "stock" car with 32,000 miles. My car has had only me in the seat and has seen some abuse. When something breaks I look into the rear view mirror to see who did it.


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## Goat51 (Oct 27, 2015)

Thanks Svede. I was fortunate to speak with and develop a relationship with the original owner. I have all the paper work, receipts etc... including original sticker and fun dyno chart after he had the CAI and AirRaid PowerAide throttle body installed, which creates a whirling vortex of air terror! (increases torque by 500ftlbs and gas mileage up 90mpg...actually I don't think it does squat, but it's cool to talk about..ha!)

So I did my tranny research, found a great shop from the Minneapolis Corvette guys and I'm going to have the tranny fluid changed on Friday. No flush though ;> 

After I've gone through the variables, new trans vs rebuild from FLT Finish Line Transmissions | Performance Transmissions | Torque Converters | Transmission Parts | Transmission Service. (this is where they would send it) or add a cooler, I've come full circle again, which is I don't want to get the Horsepower addiction (no knock on the guys that love it, I've got kid braces to pay for). I didn't wreck the tranny, the car just isn't designed to be driven like that. I've found some limits and that' fine with me. It's plenty damm fast stock! What I like best is that with the cut-outs opened 50% with the Magnaflow exhaust, I think it sounds really cool, what I've wanted since I was a youngster. So I'm staying the course. https://www.facebook.com/MinneapolisMotoringClub/?ref=bookmarks see video and there's a pic of me with the strut

Last week at the gas pumps, I talked with a guy who had a black 2014 911 carrera S. It looked cool, but sounded like a girls car...ha!
Cheers,


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## svede1212 (Nov 1, 2005)

Hope it works out for you. My suspicion is the trans shop will have to fix it. Autos rarely fix themselves with easy fixes


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## Goat51 (Oct 27, 2015)

Trans Update: i went to Doug Rippie, he's had National write-ups for Corvettes and has been in business 30+ years. We drained the tranny, the fluid was not burnt, very clean, no metallic shavings...it looked really good. We replaced the filter and gasket. Doug listened to my events and said he's heard it before. Only a Tranny cooler would be the long term fix, (same as Svede) or don't drive that fast...ha!

So my fix is to relax on the pedal. No problems since. 

Minneapolis / St. Pau, MN guys...Doug Rippie Motor Sports...He's got a great rep. and the MN Corvette guys use'em. Also Boos Automotive is used by those Club Members.
Cheers!


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## svede1212 (Nov 1, 2005)

Thanks for posting an update. A lot of guys ask questions and then we never know what happened.


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