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2015 GMC Sierra 2500HD 6.0L

General Tech Support Questions

Moderators: mikel, 06MonteSS

Post Mon Dec 02, 2019 8:11 pm

Posts: 2
I am looking to tune my GMC sierra to get better fuel economy. I just purchased the Diablo Sport Intune I3. I run 87 octane, and tires are LT265/70R18 which is only one size up from stock. I bought the truck used so I am not sure if it has been tuned in the past. I just bought a K&N cold air intake which I have not installed on truck yet. I am only getting 10 to 10.3 miles a gallon max. I have run 89 octane and fuel mileage stays the same. Truck lags when you hit the gas. No power at all. Please help me tune this truck. Any suggestions would be great. Thanks!

Post Tue Dec 03, 2019 1:06 pm

Posts: 56467
Location: DiabloSport World Headquarters

Id suggest trying the 93 tune if you are looking for more power, it will make the best gains when used with 93 fuel.
Mike Litsch
Powerteq Customer Service Manager
Diablo Tech support by phone:
M-F 8:00 AM to 5:00 PM EST

Post Sun Dec 08, 2019 10:27 pm

Posts: 2
HI Mike. Where do I find the 93 tune. Thanks!

Post Mon Dec 09, 2019 2:04 pm

Posts: 17780
Location: CT

Tune Vehicle - Advanced Mode...

select the ECM tune called "Diablo Tune" - that's the 91/93 octane tune...

and then choose the Firm Shift tune for the transmission/TCM tune...
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 -- -- --

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