Had a chance to size up the 2500HD ZR2 today. It's a big boy and sits nearly as high as my previous HD with 6 inch Cognito lift on 35s. It's four inches taller than my 1500 ZR2 at the door handle. Not sure I think the tires/rims sit wide enough for me. I think some 37'x 13.5 tires are in order.