performance upgrades for my 3500 express 6.0L

[dmosley73]

what's the  most efficient route to gain some horsepower for my 2015 express 3500 6.0L, to ensure being able to tow 8k lbs with efficiency?  would a programmer be sufficient or would i  possibly have to consider a cold air intake kit? i know air flow helps intake and exhaust wise, but if you guys have any tricks you've learned, sure would be appreciated. Carvana is giving me a crazy number for my 2016 silverado 2500 HD, so i have to use my van until i get another truck. according to a local chevy dealer, he says third quarter he is going to get hit with an influx of trucks(due to computer chip shortage now and being behind),so i will be using my van majority of the summer until the supply increases, hopefully dropping the prices on new trucks.  thanks in advance for any and all advice.

[CamGTP]

Tuning it can help and so would putting some more aggressive gears in the rear end.

 

I don't know what you have now though. They might already be 4.10's.

 

A intake won't do you much at all, people just do it for better intake sounds.