Guys,
I have read on other threads that you should not warm up your diesel on a cold morning start because of soot build-up, especially on the 6.7L. At times, I have used the high rev only to get the fluids moving and only for 1-2 minutes.

Now from where I live, I can be on the interstate within a 1/4 mile; therefore, I'm getting up to 60mph while the truck is still quite cold. I've noticed that the truck will remain in 5th gear and run at 60mph for about a 1/5 mile before going into 6th gear. Shortly thereafter, the truck will begin to show warming up.

What is more harmful to my truck, warming up in the driveway, or pushing it down the interstate while cold? I guess I should point out that my drive to work is less than 10 miles. Therefore, I know that it is not long enough to complete a regen, so I'm prepared to make long runs down the interstate for a beer run.