Texas I wish! -2C or 28F here today and snow...

Here is another one for you, they say in the manual to use the exhaust brake for quicker warm ups...

So this morning the temp was -6C, I started it up, it was the typical idle speed, then about a minute or so and it went into high idle...I had the EB on, and it sounded like a jet taking off and I assume the turbo was working pretty hard as I had alot of turbo whine. I'm guessing this is not a good thing to do?

__________________
2009 Ram 2500,QC, 6.7L, Auto-6, 4X4, Laramie
2006 Hummer H3, 3.5L, Adventure PKG
1986 GMC Sierra Classic, 5.7L