2021 Sierra Denali HD Gas Modifications

craig c · August 24, 2021

Hi. I’m trading in my 2014 Sierra Denali for a 2021 Sierra Denali HD gas engine. I have a Corsa Exhaust and a K&N air intake on my 2014. I don’t think they are available for the 2021 HD. Any comments or recommendations?? Thanks

Kjduvall · August 25, 2021

Only intake I know off for these trucks (as of now) is the AFE momentum. A member here has it and it looks good , just search that here and you'll prolly find that thread. As for exhaust, I'd just pick your favorite sounding muffler and have it attached with 3.5 in stainless connections. I'm getting ready to go to my buddy's shop and do a borla xr1 6in round body/15in case length put in place ove stock unit. I also bought two stainless 3.5in mandrel bends from summit to make the transition clean. In my opinion that's the easiest/cheapest way to make these trucks sound good

craig c · August 26, 2021

15 hours ago, Kjduvall said:

Only intake I know off for these trucks (as of now) is the AFE momentum. A member here has it and it looks good , just search that here and you'll prolly find that thread. As for exhaust, I'd just pick your favorite sounding muffler and have it attached with 3.5 in stainless connections. I'm getting ready to go to my buddy's shop and do a borla xr1 6in round body/15in case length put in place ove stock unit. I also bought two stainless 3.5in mandrel bends from summit to make the transition clean. In my opinion that's the easiest/cheapest way to make these trucks sound good

Thank you for the advise! I appreciate it!

Kjduvall · August 26, 2021

9 hours ago, craig c said:

Thank you for the advise! I appreciate it!

I would do the exhaust, with muffler of your choice 3.5in/out. And don't worry about the intake. A pedelcommander will make it alot more fun to drive (I have mine set on sport +1 and makes a world of difference), and to me is a much better bang for the buck compared to putting an intake on a truck that already has a pretty free flowing intake from the factory. If I change my intake it's gonna be a supercharger..........

GMC4Zee · August 29, 2021

Kjduvall, tell me more about the pedal commander. Does it give better off the line response? Feel like more power? I tow, will it help that aspect?

Kjduvall · August 29, 2021

It doesn't make power. It allows you to adjust pedel sensitivity, witch really makes the truck so much better to drive , it feels like you only have to hardly touch the pedal and full power is right there... It is also very adjustable, it has over 30 settings to choose from, so you can adjust it just how you want your pedel to feel. Look at some YouTube vids , and you'll see some really good reviews on it. Personally I'm sold on it, it's better than I Evan expected , and no I'm not a sales person for them, they make a good product, I think mine is a pc77.