RE: 2500HD 8.1L
Just get the truck you won't regret it.... I actually have a 2001 8.1L 2500HD extended cab as well since it was new. I can honestly tell you I have never clocked the gas mileage to get an accurate measure. Some people look at me strange when I tell them that, like I've have my head in the sand or something, but it's mainpurpose was never aboutfuel economy.The truth is I bought the truck for a purpose to tow my 5th wheel plusI like the power on acceleration because of thetorque.Gas mileage to me was neverfactor and I'm no rich boy and Idon't make a million dollars either.(In 2001 when I bought itthe price of gas was still reasonable.) Not to mention driving conditions vary greatly depending where you drive and the type of driveryou are out on the road. If you put your leg into driving this bad boy you're gonna get there quickly but also burnsome fuel. If you don't blast aroundyou are probably going to be closer to the 6.0 as others have indicated.I will tell you that you are about to buy one of the best trucks I have ever owned. Do not hesistate, do not have second thoughts, just get the truck and enjoy it...