Done some research and seem to be more lost then when I started. Never had a newer truck or even a fuel injected one. Anyways, Trying to find a tuner for my 4.3 Silverado custom 2018. From what I have gathered even the 4.3 has AFM witch knocks it down to 4cly? Never seen a light that others talk about in my dash not sure it it applies to me. If you guys say all do I want a tuner that will delete that. Next I’m running 37s so need one to put my tire size in. Last I keep reading about E85 Tunes witch confuses me. Uses a different gas with a tune to crest power but to identify if my truck can take that gas it says on the gas cap witch I don’t have or rear window. Go my truck tinted day 1 and have no idea about that. My objective of the tune is to have my truck finally shift right and get as much acceleration as that thing can without motor or gear work. Don’t care about mpg or topend speed. If you took the time to read this I really appreciate it. Been wanting a tuner for weeks just started reading and ever post just left with more questions! Thank you guys!