The truck is 3 months old with 2100 miles. At 900 miles I installed an Ultimate PD and ASP underdrive pulleys. Yesterday I had the stock muffler replaced with a single 3" in, (2) 2.5" out turbo muffler. Should I reset the PCM or will it "relearn" and teach itself?? If I should reset it, which fuses do I pull.

Thanks

 

You don't have to, it'll adjust after a few days, but it won't hurt either.
Turn key to run, pull ECM I and ECM B, wait 5 minutes, turn key off and put fuses back in. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />