2017 GMC Sierra PredX no TCM tunes?
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mdballer54
- Posts: 2
- Joined: Tue Oct 14, 2025 1:50 pm
2017 GMC Sierra PredX no TCM tunes?
I finally got my predator X running after the original didn't work. I am able to load the 87 tune. But I'm not seeing the ECM/TCM tunes that are shown in the demos and videos. All of the product descriptions show this should be an option. I've run the updates on the firmware etc. Am I doing something wrong or is this not an option for this truck?
Re: 2017 GMC Sierra PredX no TCM tunes?
If you have the 8 speed tranny, you won't see any TCM tunes, because the 8 speed tranny in the 2017/2018 trucks is not supported at all... can't tune the 8 speed TCM/tranny... you can only tune the ECM/engine...
06MonteSS / DiabLew Tune

2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net

2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net
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mdballer54
- Posts: 2
- Joined: Tue Oct 14, 2025 1:50 pm
Re: 2017 GMC Sierra PredX no TCM tunes?
That's my issue. 8 speed. Wish I knew that before I made the purchase. So what am I getting with the 87 tune if it can't change shift points? Just some adjustments to the fuel tables?
- mikel
- Posts: 58674
- Joined: Tue Jan 16, 2007 1:17 pm
- Location: DiabloSport World Headquarters
- Contact:
Re: 2017 GMC Sierra PredX no TCM tunes?
the ECM tunes are where the power comes from. Timing, fueling, torque management, throttle control, etc.
In 2017, GM locked the TCMs making it difficult to tune them. We are working on a possible solution to allow for tuning them.
In 2017, GM locked the TCMs making it difficult to tune them. We are working on a possible solution to allow for tuning them.
Mike Litsch
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST
[email protected]
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST
[email protected]
Re: 2017 GMC Sierra PredX no TCM tunes?
Given that the 2017 8-speed TCM is currently locked, what specific hardware or send-in service is now required to get the TCM unlocked so it can be tuned? Does DiabloSport or one of their partners offer a reliable method for the initial TCM unlock process for this specific 2017 model, or do I need to go through a company like HP Tuners first?mikel wrote: Thu Oct 16, 2025 10:06 am the ECM tunes are where the power comes from. Timing, fueling, torque management, throttle control, etc.
In 2017, GM locked the TCMs making it difficult to tune them. We are working on a possible solution to allow for tuning them.nulls brawl
Last edited by Lexa321 on Thu Jan 29, 2026 10:22 am, edited 1 time in total.
- mikel
- Posts: 58674
- Joined: Tue Jan 16, 2007 1:17 pm
- Location: DiabloSport World Headquarters
- Contact:
Re: 2017 GMC Sierra PredX no TCM tunes?
we dont offer anything today, but we are looking into a solution that should be better than the available options today.
Mike Litsch
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST
[email protected]
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST
[email protected]