Able to add locking diff??
 

So I bought my truck without the fx4 package, but I've been thinking I'd like to at least have the locking diff. Is it possible for me to just buy that itself and get it installed in the truck still?

Able to add locking diff??
 

What do you have today? Open differential or limited slip. If you have the limited slip I'd recommend sticking with that unless you do a lot of off road driving.

Hmm I'm not sure, whatever it comes as stock is what I have...

Sounded like you have limited slip and are looking for the e-locker, this was a stand alone option as well without the fx4 pack, I upgraded to the 3.55 elock from the 3.31 limited and it was $400 Canadian

Also if I had to guess this would be super expensive and also would require the actual control inside the truck ;(