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Programing New Gear Ratio?

  • Firebumb58
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3 months 1 week ago #91867 by Firebumb58
Programing New Gear Ratio? was created by Firebumb58
Hello Everyone,
            I Have a 2018 Chevrolet Silverado and have changed my front and rear Differentials to a new gear Ratio! My Speedometer is now off and Cruise Control do not work correctly.
Can anyone please tell me what is needed to reprogram TCM or ECM to the correct gear ratio?? Any help would be greatly appreciated.
                                                                                                   Sincerely,     Tom Ringrose
                                                                                                                            Firebumb58@yahoo.com

 

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  • Chad
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3 months 1 week ago - 3 months 1 week ago #91870 by Chad
Replied by Chad on topic Programing New Gear Ratio?
I have never updated a gear ratio calibration but, I think the place to start would be to login to Techline Connect SPS2 and browse the calibration files for the ECM and TCM.  You may have to uncheck the "Show only latest calibrations" box, if available. Look for "Axle Ratio" or "Final Drive Ratio". 

To use SPS2, you will need to create an ACDelco TDS account and purchase a VIN based subscription. You will, also, need a J2534 pass-through device. 

www.acdelcotds.com/subscriptions
 
"Knowledge is a weapon. Arm yourself, well, before going to do battle."
"Understanding a question is half an answer."
I have learned more by being wrong, than I have by being right. :-)
Last edit: 3 months 1 week ago by Chad.

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  • Noah
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3 months 1 week ago #91874 by Noah
Replied by Noah on topic Programing New Gear Ratio?
Some aftermarket tuners may be able to do this also if SPS is not an option for you.
When I cam swapped my Hemi for a non DOD camshaft, the kit came with a Diablo Sport hand held tuner that has the ability to, among other things, update the gear ratio and tire size.
"Ground cannot be checked with a 10mm socket"

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