Assuming this is a 4WD truck we're talking about...
If the kit is only 3 inches (and it's not a body lift) then it's almost certainly a torsion key kit for the front, which is a complete waste of money. You can crank up just as high with the parts already on the truck, but cranking the keys up that much will ride very harshly and tear up front end parts pretty quickly. I would save your money.
To get any kind of decent suspension lift for these trucks (4WD) you really need to go with at least a 4"-6" kit with a front differential drop to keep the CV angles reasonable.
^^Rock solid info right here. key, crank, upper control arms kits, or some combination thereof, create more problems then they solve. On going tire wear issues from not being able to obtain acceptable alignment specs, accelerated parts wear including breakage of ball joints, tearing up cv boots one after the other, etc. Want lift, spend for a proper 4"-6" kit and be happy. Rough Country RCX , Zone, etc. A a 3 inch full on crank with or without upper arms will make these trucks ride like a jack hammer. Guy's will buy the key kits and come right back, How do I fix the brutal jaw snapping/vertebrae cracking ride. If you can't because you already bought bigger tires , then what..If you've never experienced your cup holders tossing drinks out them going over a parking lot speed bump with one max cranked is a good way to experience it. I can't even count the times I've heard, "well I only want 3" or even more famously "a little bit" only to later find out they have it cranked as tight as it can be wound. Best advice, figure out where you want to be instead of the cheapest appearing way to get there. If you need 3", a proper 4" kit still the better option for all intents and purpose's.