I have just turned 70k in my 2003 Denali and its been a solid truck. Regular maintenance and I am told by the lube guy that there is a very small fluid leak from the intake. This is common in Vortec engines according too him. I guess overall I have been very impressed I just hope they have used better materials for the interior of newer models. I don't see myself ever replacing my truck it has been a good ride so far.