LOL...I go WOT every time I get on the freeway on-ramp in the X5. That said there is a difference between driving a car responsibly and beating on it. If you want the car to last you don't want to thrash the engine and drive-train. The X5 is a sport utility and has a wonderfully designed engine which if maintained properly will last several hundred thousand miles.

The car is designed for short bursts of WOT for passing and as I said accelerating such as getting on the freeway. If you exceed that usage you will surly reduce the life of the engine and other components which are not designed for that type of extended stress.

Funny thing is I'm WOT in the X5 more than my SRT-8. The SRT-8 makes a lot of noise and gets up to speed way too fast to be practical at WOT. It's fun as heck but not very safe in every day driving around traffic where the X5 is comfortable and manageable wide open.