New Torque Converter installed - What a difference!
#21
Safety Car
Thread Starter
Is there an optimum cruise control speed setting and/or RPM level that needs to be set in order to watch the RPMs to see if they move up and down?
What exactly does "slow to go into the gears" mean? Rough shifting? RPMs climb to 4000 but it doesn't shift to the next higher gear?
What exactly does "slow to go into the gears" mean? Rough shifting? RPMs climb to 4000 but it doesn't shift to the next higher gear?
Slow to go into gears. When I first got into my car and placed it into reverse to back out of the garage, the transmission would not shift and I would just sit for several seconds before the car would start in reverse. Also after the transmission warmed up and I stopped to do some shopping, maybe 2hrs, when I came out and started the car and placed it in reverse, it would jerk into gear. So I guess slow to go into gears and also jerking into gear.
#22
Le Mans Master
Congratulations on getting your issue resolved!
Did the dealer list the part number for the new converter? Sometimes they don't but I thought I would ask anyway.
I can see the techs getting very good at doing this swap!
Did the dealer list the part number for the new converter? Sometimes they don't but I thought I would ask anyway.
I can see the techs getting very good at doing this swap!
#24
Melting Slicks
Mine did that, cured last November with a new TCM software update and subsequent "fast-learn" procedure. Not sure when the update was released, but it was sometime last summer. What is the build date of your car? Only cars built after Sept. 29, 2014 can accept this update, I'm told.
Last edited by iclick; 02-10-2016 at 10:02 AM.
#25
#27
Picked up my 2015 A8 from the dealer today after they installed a new torque converter. They also replaced my transmission filter. WOW what a difference. It is like driving another car. I have no symptoms of a bad torque converter. My transmission shifts very smooth and you can't tell when it shifts from V8 to V4 and back. When I slow down to stop, the transmission shifts smoothly and you do not feel the transmission down shifting. The RPM's at constant speed DO NOT move up and down. I enjoy driving my car again. The service writer said if you don't eventually have the bad torque converter changed out your transmission will fail. He feels GM at some point will have a recall. You would think it would be cheaper to replace the torque converters than replace transmissions.
Last edited by Orange Z06 Girl; 02-06-2016 at 02:11 PM.
#28
Safety Car
Thread Starter
Do you think an aftermarket converter would help? We have a 2015 z06. Our first a8 failed at 13,000 miles in September. After that They put a new a8 in. When it got a couple thousand miles it started shifting into reverse and first hard again. We took it in and they reflashed it and said it was because our trans learned how to shift hard when it was learning itself. The reflash did help the problem but we parked it two days later so not sure how long that fix will last. We have since gone wild with mods....and the converter is on our list. I finally found out about the circle d one yesterday. https://www.corvetteforum.com/forums...-the-8l90.html
#29
Burning Brakes
My Z51 Coupe is an early 2015 with the 8-speed. So far I have not noticed any issues with the transmission but it only has 4,000 miles on it. It is currently in hibernation mode in my heated garage and won't see daylight until April. I have not been back to the dealer yet to reflash the transmission or the PDR. In fact, it has never been back to the dealer. I have a lift and do my own oil changes. I replaced the oil filter only at 300 miles to lower the oil level and then replaced oil and filter at 500 miles as recommended.
I intend to take it on the highway in the Spring and turn on the cruise control to see if it surges at all. I don't usually use cruise control except on a long trip. If I do notice a problem I will try to get the dealer to replace the torque converter before the transmission is damaged. Maybe GM will issue a recall before then but I won't hold my breath for that to happen!
I intend to take it on the highway in the Spring and turn on the cruise control to see if it surges at all. I don't usually use cruise control except on a long trip. If I do notice a problem I will try to get the dealer to replace the torque converter before the transmission is damaged. Maybe GM will issue a recall before then but I won't hold my breath for that to happen!
Last edited by FredC7; 02-06-2016 at 06:44 PM.
#30
Congrats.
Yours is the first report I've read, from anyone who has replaced TC. Glad it worked out so well. I have all the symptoms, and have an appt. on Tues. with a local dealer. Just wondering if there has been any downside at all, like new rattles, leaks, misaligned body panel, etc. How long did the dealer have the car?
#31
Safety Car
Thread Starter
Yours is the first report I've read, from anyone who has replaced TC. Glad it worked out so well. I have all the symptoms, and have an appt. on Tues. with a local dealer. Just wondering if there has been any downside at all, like new rattles, leaks, misaligned body panel, etc. How long did the dealer have the car?
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LB001 (02-07-2016)
#32
Maybe some members who had a successful reflash will post. If you have a bad torque converter, let the dealer install a new torque converter for you under warranty. It would help to go to a dealer who has diagnosed torque converter failures and their tech has replaced C-7 A8 transmissions or torque converters.
#33
I had to find a dealer who had already diagnosed several torque converter failures and he had discussed the solution with GM. As I have mentioned, the first dealer I took my car to said nothing was wrong with my transmission. No downside, have not noticed any leaks, rattles and I did check the rear bumper closely because it has to come off to remove the tranny. The dealer kept my car 4 days; however, they decided to change my transmission filter and had to overnight it. I did ask the tech when he removed the tranny filter if he observed any metal filings in the pan and he said no filings were observed. So apparently the bad torque converter does not damage the transmission. Good luck with your dealer!
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Formula52 (02-09-2016)
#36
Le Mans Master
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767guy (02-09-2016)
#38
Intermediate
My 2015 Z51 A8 with ~16,000 miles was having the EXACT issues yours was with the vibration, literally exactly as how you described it. I took it in last week for an oil change and mentioned it and they diagnosed it as a bad torque converter. They had to order one but said it was safe to drive and wouldn't do any damage to the car in the meantime. I got the call yesterday that it had arrived so I'm dropping it off Thursday morning to be replaced. Supposedly they can do it in one day. I'm hoping my results are as good as yours were!
#40
I wouldn't be too glad, because as of October of last year every single 8L90 that leaves the plant comes equipped with the new TC that they are talking about in this thread.
So if you haven't bought a C7 yet, this is a non-issue for you.