Mine is a 3" block with an add-a-leaf ... ANything bigger than 4" is not recommended.

 

i have a 2002 ram with a 4.5 in procomp lift and a set of 35 12.50 18 bfg mud terrains the only problem with mine is that i want a set of 38's but there is no lift big enough and i am not doing a body lift.

 

Yes then you have a problem. The only way to get 38's to fit would be a body lift.. Everyone else does it, what is stopping you? You just have to know how to do them right. Don't use Urethane blocks, use steel blocks, and weld them to the frame and body so that it cannot come loose... Just do it right, and everything should be okay.

PErsonally I think 38's are too big anyway, unless all you do is mud pits.