A member here, Neuler, is running 305/55R20 Nitto's without a leveling kit.

I am still debating between 1.5" AS or 5100's on the 1" setting. I just want some of the rake gone, don't want it to be perfectly level.

 

I just put a 1.5" kit on my 2005 F150 supercab and it's perfect for me. I still maintain a little rake and the truck levels out with a load. I think a 2" would have leveled me completely but I'd definately sag with any sort of load in the bed or when towing.

I wouldn't suggest using the 2" or 2.5" without using an AAL or airbag if you're planning on hauling or towing anything more then a couple hundred pounds.

The ride is great, actually better then before - but that's due to the new 285/65-18 BFGs that I put on at the same time.

 

ive had the 2" and the 2.5" AS kits.. if you put them next to each other you can barely tell the difference... there a lil more than 1/8" apart.

 

I've been running the AS 2.5" kit for about 2 year s now with no issues. It still rides like OEM. As for tire size? It all depend on the wheel size and backspacing. I know for a fact that 305/55/20's will fit with a AS. I've seen plenty of them. If you go with a 4.5" backspace, that is where you may run into issues.

 

Hey digg, I'm thinking about the same setup you have......the 2.5 AS kit and the AS block. Was wondering how that setup worked out? I don't mind a little rake. Do you have pics of your setup?