I had a toytec lift on the truck when I bought the truck. I removed that stiff ride and installed the 5100's. I was informed that it was a 2" kit how ever it was a 3-1 so I put the 1/2 spacer on top of the 5100's. Everything I have read is a no no. Well I have put 13,000 miles on it from last July until now and no problems. As far as wheeling goes not really unless you can say pulling trees up in my inlaws pasture wheeling. I did mode the diff drop a little and got better cv angles.
You are at the max that I'd recommend for the stock suspension. Maybe you can squeeze out another 1/2 of lift with a top plate spacer?? But your alignment, suspension angles, etc... are gonna be too extreme!
Just go with a 5" lift and if the urge hits your? You can go to 7" using the 5100, and a bigger rear lift!
Problem 1. The max shock/spacer/coil over lift you can get by with, without changing UCA is about 3 3/4" in the front (in order to get front end aligned). You're probably around 3" now. So the next 1" will be expensive. It doesn't matter what combination of spacers and coil overs you can come up with. Once you get to 4" you will need UCAs.
Problem 2. If you're 4x4 3" lift is the max recommended without a drop bracket lift (typically referred to as a suspension lift). Anything more than that and your CV joints start binding.
Problem 3. For the 1-2" body lift- as far as I am aware Performance Accessories makes the only body lift to fit our trucks. Last I checked it comes only in a 3" kit (I believe it's part number PA 5633). Not a problem other than being more lift than you have expressed interest in.
If you're 4x2 you don't have to worry about CV joints and can get at least 4" by stacking and adding UCA. Additionally if you're 4x2 you can add spindles for 3.5" and combine with whichever shocks, coil overs, and/or spacers you want.
If you're 4x4 it's time to get a body lift or purchase a suspension lift.
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