8 Speed Transmission

[Zach]

Did you send us your TCM calibration?

Please email me your info file

zhill <at> powerteq.com

[toneyjay]

Just sent.
I previously sent it to tech <at> diablosport.com

[Zach]

I haven't received it and tech can't seem to find it either.

Please just post your info file up here.

[toneyjay]

TCM__UnknownBackup.grg

[Zach]

It looks as though I never received that file for processing. I still haven't received the file you tried to email me today as well....

For what it's worth, your vehicle is not currently up to date on calibrations. If it were, you'd already be supported on the latest tune database. GM has a ton of calibration fixes out for the 8 speeds. You can see the list for your vehicle attached.

I will be adding support for the calibration you posted, it will likely be next week before another tune revision goes out though.

Capture.PNG

[toneyjay]

Funny, you would think they would have updated it 2 months ago when they replaced my torque convertor. Thanks Zach. I will be waiting.

[jay p]

There is a TSB for hard down shift to 1st gear. If your truck in still under warranty take in to dealer and complain about hash 1st gear down shifts. That should get you the current TCM firmware.

Jay

[toneyjay]

Thanks. I still have to take it in for the safety recall. may see if I can line it up.

[Novarox71]

I just got access to control the parameters on the 8 speed transmission, is there adjust ability with Torque management? I don't see it in the parameters list, thanks.

[Zach]

I just got access to control the parameters on the 8 speed transmission, is there adjust ability with Torque management? I don't see it in the parameters list, thanks.

No, disabling the torque management on these units results in poor shifting and can eventually lead to broken parts.

[jamesacastro]

Thank you for giving us the ability to touch the TCM. Long time coming but worth the wait.

Now that the pleasantries are out of the way I have a couple of questions.

If GMC ever comes out with another TCM fix will we still be able to re-tune?

Are there specific recommendations for those of us experiencing the "clunk"? I ask because last night, even after the tune, I felt the dreaded clunk again. As maddening as it is, my expectations of Diablosport are not to fix an issue of GM's rather perhaps to smooth it out a little.

Thanks again.

Jimmy

[Tradetodeath]

Now that you have 8 speed supports, is the 2016 CTS-V coming soon?
thanks,
TTD

[mikel]

Now that you have 8 speed supports, is the 2016 CTS-V coming soon?
thanks,
TTD

since we have an ATSV, thats happening first currently, but likely get to the CTSV shortly.

[Zach]

Thank you for giving us the ability to touch the TCM. Long time coming but worth the wait.

Now that the pleasantries are out of the way I have a couple of questions.

If GMC ever comes out with another TCM fix will we still be able to re-tune?

Are there specific recommendations for those of us experiencing the "clunk"? I ask because last night, even after the tune, I felt the dreaded clunk again. As maddening as it is, my expectations of Diablosport are not to fix an issue of GM's rather perhaps to smooth it out a little.

Thanks again.

Jimmy

Yes, we will continue adding support to all new TCM files GM offers.

Unfortunately, there's not direct fix for the clunk. It's something the torque management should take car of from the factory but does not. If we come up with a solution, it will be rolled into all of the tunes.

[White Denali]

So for those that have tuned your 8 speeds is there much of a difference from the stock settings? Is shift firmness better, does it shift at a higher rpm at wot, and does it still shift all the way up to high gear by like 45mph? Funny nobody's came back to rave how good it is