Tuff Country Lift For Gmc 2500hd

[sascraggs]

I am wanting to install a Tuff Country lift on a GMC Sierra 2500HD 08 model. I want a 4" lift and Tuff Country is the only manufacturer I have found to make a 4" kit for 2500HD's. I know everyone uses a 6" but I only want to run 33X12.50's on 18" wheels. I do alot of towing and it can be heavy. Also which kit is better and what is the difference between the 3 piece and the one piece sub frame kits. which is better for a HD application? Other kit recomendations or other brands of 4" kits? thanks.