Been looking around at new trucks lately, especially with the GM discount. One salesman suggested that because I drive 25,000 miles per year and pull a stock trailer for a good number of those miles I should consider a diesel engine rather than the vortec 6000. I'm looking at the Sierra 2500HD with bells and whistles ( this may be the last truck I buy). There is about a $5500.00 difference between gas and diesel. The diesel seems to make more sense but thought I'd get more input. Thanks for your help!