A6 expert needed for 08 Vette

[xtreme3881]

Need some expert transmission mechanics here. Here is what we are dealing with

-2008 Corvette Z51
-Automatic
-11k Miles
-Clean VIS report before purchase

Had some issues with the car shifting really hard into drive when the transmission was cold, so I had the dealer do a TSB. They did TSB = PIP-4395E, and fixed the issue with hard shifting. Then got an engine code a day after I got it back, and they said it was the PCM. They then proceeded and ordered the following. Also here is all the work they did between both services for the TSB, and the PCM

-Replaced 1-2-3-4 and 3-5-R clutch fluid seal rings per doc 2492878
-R&R Trans pump and valve body
-Valve body
-Replaced control solenoid valve
-Transmission control module Assy.
-Programmed trans control module
-Programming code 18652

Now the car shifts much better from Park to drive. Granny/Spirit driving seems good as well. Now the issue I am having is when I give the car gas to the point it will down-shift, it seems to wait maybe a half second before launch. I am NOT talking WOT, but just enough to give it enough gas to down-shift, and launch. It’s like it doubles pumps, and takes off like a bad out of hell. It’s not the TC/AH/….it gets worst in sport mode, and even if I hold the TC button for 5 seconds to turn everything off I am still not giving it enough gas to burn rubber.

Another example is I was playing with this to see how everything was working. I found a street to test on, and get to about 30mph and give it some gas. As soon as I did I seen a cop, and let off the gas pedal ASAP……Well the RPM stuck at 5.5k-6, and took good second or more to slam back into gear. During that second I had NO throttle control, and was like the car stalled. Drive seems to be the cleanest mode to be in; Sport is terrible; Paddles scare me to think the transmission is going too exploded. Since I got the car back I have had some times of a dead peddle. Meaning just driving granny style, and get no throttle response. For example driving back from lunch cruising down the road at 35MPH, speed increases to 45mph so I give it more gas and does nothing, but finally kicks in?

Here is a paddle example
Start in 1 40% throttle through each gear, and here is how it shifts.

1…2……………6k…5.5k….5k…………….3 and when it hits 3 it’s very sloppy.

I don’t care for the paddles to begin with, but it’s good to test things. Could this be because after the program it needs to relearn? The dealer is about to order a new transmission because this is ridiculous. Owned the car for two months, and been in the shop for 1.5 months. Also on my service ticket it looks like the place in the correct Dexron VI fluid, but did he do enough??He used (2) 1 gallon jugs, and 3qts for a total of 11qts. Any help is greatly appreciated.

[c4c5specialist]

HI there,

There are keys here that must be addressed.

#1, you havent owned it since new so that means there is no way to tell or know how the vehicle was driven, if it was abused or anything else.

#2, did the dealership itself overhaul the transmission or did they sublet the repair ????

#3, there is an element of torque management that must be understood here. Agressive driving, abrupt on and off throttle transitions will cause torque management to kick in and REDUCE the response time of the throttle plate opening to reduce torque shock to the driveline and transmission damage.

#4, the reduced throttle response could be simply a throttle pedal sensor truthfully if your just cruising and cannot lean into the throttle with no increase in vehicle speed.

#5, OR it could be slippage within the transmission assembly.

If they are going to get you a SRTA, I would let them. Its obvious that there is an issue and only a few hours of testing with a Tech 2 attached will allow the accurate data to be reviewed and the problems be understood.

Allthebest, c4c5

[xtreme3881]

@c4c5specialist

1. You are correct I am the second owner of the vehicle so I dont know if it was abused other then what I can see.

2. The dealership used a technician at there dealer to do both the TSB, and the PCM repair.

3. I would agree with this statement, but like this morning I was driving to work, and went into Paddle mode. I drove really calm, and RPM's no higher then 3k. Started in 1, then went to 2, and when it came to 3 it floated and jerked in. At this point the trans tems was around 100 degrees.

4. I hope its this, be quick and easy

5. Based on this question and the others your stated, could it be a bad program to the trans? Meaning using the Tech 2 he use the wrong program update? You can see in my first post the code he used to update it. Last but not least here is what the Service manager I have been dealing with told me a few days ago when I messaged him right after I got it back. Oh and by the way, whats "SRTA"?


John,

Jim is not here yet, also when he had the transmission apart the first time and then the pan dropped the second time, we did not see anything inside of the transmission that would indicate an internal transmission problem. This has got me stumped and I will check with Jim and get back to you.

I would continue to drive it and if it acts up one more time, then my suggestion at this point would be to bring it back here again. I will then drive the car over to our Joliet store and talk to the service manager there directly and ask if there transmission expert can look at it for us. I know you have probably not heard good things about our Joliet store, but that is because of the service advisors and management, however they do have a good technician that is very good with these transmissions, so it might not hurt to get a second set of eyes looking at it. ( just a thought).

I understand how you would be very upset at this point John but, I think you have a pretty easy going demeanor, like myself and just don’t want to start screaming at somebody and I appreciate that.

One way or another I will make sure this car is fixed so you are happy with it. I will also talk to my GM rep today and find out if it is possible to just put a new transmission in the car for you because of everything you have already been through. Based on what I have seen with GM and the way they want transmission claims handled it might be a hard sell, but I will try.

Thanks again,
Dan

[c4c5specialist]

HI there,

SRTA

Service
Replacement
Transmission
Assembly.

Lets see what they come back with.

Allthebest, c4c5

[xtreme3881]

Going into the dealer now...I will keep this thread going with updates. Thank you so far!

[xtreme3881]

@c4c5.....OK, its at the dealer. Is there any modes that I should request they check using the Tech 2? Since its going to an in-house trans tech expert I am sure they would check everything, but you have anything specific? This did this Programming code 18652 already...You know what that is?

Thanks,

[NORTY]

It's times like this that I think of the good old reliable Turbo 400...

[LLC5]

Originally Posted by NORTY

It's times like this that I think of the good old reliable Turbo 400...

And 8-12 mpg in a 400+ HP engine, if you were lucky! :)

[markw8]

And we think of then as the good ol days.

Mark

[c4c5specialist]

Originally Posted by xtreme3881

@c4c5.....OK, its at the dealer. Is there any modes that I should request they check using the Tech 2? Since its going to an in-house trans tech expert I am sure they would check everything, but you have anything specific? This did this Programming code 18652 already...You know what that is?

Thanks,

HI there,

The programming code is ONLY a confimation that a programming sequence was done by a technician. This is required to be documented so that the dealership is paid for programming the transmission control module.

GM only allows programming the control module with the latest control programming.

In truth, a dealership technician only is able to update with the latest, they cannot upload a superceded calibration.

I personally believe that you have been served well to this point. Some 6L80 issues can be difficult to find and I believe if you continue to allow your dealership to evaluate all options prior to a SRTA unit, you will do ok and your car will be repaired correctly.

Without the vehicle in front of me, there is no real way to assist further. This is obviously a very in depth issue.

There has been the bulletin that was issued, replacement of the valve body and control module, a PCM so I dont really know what else they can do short of removal of the transmission and complete teardown to evaluate the possibility of a hydraulic leak point.

Please keep us posted, c4c5