I purchased a 08 2500 sierra lifted and it had the autocal and dsp5 switch in it. I never could tell the difference after I tried reprogramming the tune in it numerous times and still don't notice any difference. I have already replaced the switch witch did not help. I believe I erased my autocal when I tried to erase and update the firmware. I don't see my DSP5 full anymore.
Thanks for any help.
Thanks for any help.