2005 Deville Hard Shifting
 

Hi. I have a 2005 Deville with 89,000 that was well maintained and not abused. After a car wash it started slamming into each gear, including reverse and park. I previously posted about it and received some excellent advice. Unfortunately, it did not resolve and I took it to the dealer. After a two week wait, they today told me that there was a faulty wire harness in the transmission and a bad flywheel clutch. The estimate was $2300.

Does this sound like a reasonable evaluation and estimate? Any suggestions on where I might take it for a second opinion? Does it make sense to take it to another dealer or will they see the same computer codes and give me a similar estimate?

I will take it to Autozone and get the computer codes to post as soon as possible. Thank you.

Craig

I have seen failed internal wiring harnesses, so that is possible. I have never heard of a "flywheel clutch", and I really hope that is NOT what they actually said to you. If it is, then I would definitely take the vehicle somewhere else. If, however, you mis-spoke on the terminology, I would have to assume they may have told you the Torque Converter Clutch is bad/failing, which is extremely common on those transmissions.
$2300 for the trans repair/rebuild is very good, or about average, at least for the area I am in.
Still can't explain why it would all of the sudden do this after washing the car, unless water got into a connector somewhere. GM wiring and connectors are not the best, so corrosion, and other types of wiring failures are all too common....:(

Thank you
 

Thank you for your post. I did, indeed, misspeak. It was the torque converter clutch. I don't know what I was thinking. Does the transmission have to be removed and opened to repair the torque converter clutch?

Craig

Unfortunately, the trans will need to be removed to get to the torque converter. It is bolted to the flywheel on the engine, and it is what transfers power from the engine to the transmission. The real problem with most torque converters on this transmission is not really the converter itself, but leaks inside the transmission that cause the converter to fail. Replacing the converter without addressing the real problem will only work for a while....it will eventually have the same problem down the road.
If you look thru this Transmission forum, you will see MANY threads on this problem, or just do a search for "P0741", or "Torque Converter"....it is the #1 problem with the 4T80E transmission.
There are two specific seals inside the trans that leak, and cause the converter to no longer be able to achieve full "lock-up". This usually results in a melted TCC(torque converter clutch) solenoid, since the PCM is trying to get the slip down to a manageable level. With the current going to the solenoid to try to keep the converter clutch from slipping, the solenoid eventually overheats, and fails. Replacing the solenoid and/or converter is not the real fix....the seals need to be replaced as well.

Any time a trans code is set in the PCM, the trans will shift firmer...it's a "failsafe" mode to keep from doing any more damage to the trans.

Thank for that great explanation. I have a much better understanding of what is going on. I'll be taking it back to the dealer for the repairs.