Originally Posted by kyleTRDtaco12
The diff drop is actually ok to run... it will save your front axle CV joints... they aren't a bad idea IMO but thats always up for debate on here depending on who you talk to. The dif drop may also save you an front annoying driveline vibe in the future... just saying.. plus, since OP said this is mainly for aesthetics, having a diff drop doesn't matter in there case, because guys on here will tell you that it exposes the front diff alittle more when wheeling which slightly affects clearance... but it wont hurt you in your situation
The diff drop is considered a bad idea because it doesn't really drop the diff, it rotates it front down instead. By doing this, the rear bearing is now higher, and more 'out of the oil'. This doesn't do anything to save your CVs as they will still be operating at, or damn near the same angle they would be without the diff drop.
OP, that kit comes with Eibach coils which are significantly stiffer than stock coils. To get to 3" of lift, you need to preload the coils by setting the 5100's to .85. Because you have a 4 banger, you likely will not need the top plates. The top plates are required to get 3" of lift on a V6 but since your front end is lighter, you might get there without them. I had those same coils on my 4x4 DCSB V6 on Bilsteins set at 0 (no preload) and they rode very firm, comfortable but firm. They could end up being a little harsh when you add more preload to them to get the lift you're looking for, especially since you have a 4 banger (lighter engine meaning not much weight to compress those springs).
As an alternative, have you considered an Old Man Emu kit with 885 coils instead? Those have a lower spring rate (still stiffer than stock) but do not require preloading to get the 3" of lift.
Also, I would recommend getting, or planning on getting new upper control arms if you want to run with 3" of lift. There is very little available adjustment to get a proper alignment at that amount of lift and an adjustable UCA helps you dial in more caster so your truck rides well on the highway. New UCA's can be had under $400 if you're patient. Check out Light Racing UCA's from Fat Bob's Garage or Headstrong Offroad.
Also, be aware, when you read threads on here, pay attention the amount of lift gained from a certain lift and which engine they have. The 4 cylinder models will gain a little more lift from the same setup and you don't want to go over 3" as that can lead to issues down the road.
Oh, and start here: