Knowles Richard
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- Apr 5, 2018
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Hello Double D & truckers I have a 2013 gmc sierra sle 5.3 SL80 transmission by putting the trans in (M) mode on shifter And then pressing the toggle switch to 5th gear This disables the AFM or v8/v4 so that its all the time v8 My truck also stays in all time v8 when in tow haul mode But its not good city driving RPMs to high on up shifts Eats Gas I got a diablo P2 and deleted that Stinking AFM. Weird exhaust noise GONE vibration GONE.Much Better performance I am happy that's how it worked for my truck hope this helps