4k is a very good budget! For that money you can get a damn nice lift if you so choose.
First off let me talk about what lifts to stay away from: Rough Country, Skyjacker, Rubicon Express and all of the other cheap lifts out there.
Those lifts are generally much cheaper, but you really and truly get what you pay for.
Now, if you want some good lifts that won't break the bank, but are highly regarded in terms of ride quality and performance, I would either go with OME (Old Man Emu) or Zone. Both of those lifts are excellent quality lifts that won't require to to spend that much. They'll perform great on-road and off-road.
If you want the best of the best in terms of pre-packaged lift kits (meaning you're not piecing a kit together yourself), I think that most will agree that Currie / Savvy and Metalcoak are not only the most popular, but also extremely good quality and performance. These lifts will run you around $2500 for the lift, plus you'll spend about $1000 or so extra on parts like a SYE (slip yoke eliminator), CV style driveshaft, etc.
So, it's up to you what you want to do. Any of these lifts will clear 33" tires just fine (and look great too!).
I personally run the Currie lift, which I am more than impressed with.