2016 Express 1500 4x4, 5.7, 3.21 rear gear ratio. So I'm looking into diff gears for when I level or possibly lift my truck and put bigger tires on. Not going huge whatever I do, no bigger than 37s. Figuring on 3.92s but I'm finding some weird info on the front differential having the ring gear welded to the carrier. Can anyone give me some more info on this and what I will need to do to change the gear ratio for the front diff? Or if I even need to mess with the front diff. Venturing into a world I'm pretty unfamiliar with. Thanks
You can get a 3.92 front pumpkin from a 2016 with the gears already installed and it's plug and play all day.
I would recommend having some sort of tuner both for PCM "engine" and BCM "cabin" to adjust for the gear ratio change regardless of your selection.
Now, if you decide 4.56 gears which I personally use and recommend along with the rest of the forum members who agree you will need the following:
2011 or older front diff (gear ratio won't matter at this time) 4.56 gears "front and rear" I use Yukon but others may recommend something else.
Front and rear master install kit. This will make everything as close to plug and play as possible.
Fluid 75-90w front 75-140w rear but you have options there. Some guys like different weights based on their use. The one's listed are pretty standard.
Optional are Diff covers (makes fluid change much easier and they look cool!)
I believe everything else will line up no issue. Brackets and stuff like that.
On my own installs, I like using new bolts for everything. Sometimes I'll have them painted to match the truck's theme.
Good luck
Either way for everyday purpose 3.92 and 4.56 hears are a lot more fun than the 3.21's