I just returned from a 4 day trip to Lake Tahoe with my new 2500HD 4x4 D/A. I noticed a groaning noise from my brakes after driving continuously for 8 hours (450 miles) both to and from the lake. Any ideas what might cause this noise? My truck only has 3500 miles on it and I was not towing anything when the noise occurred and it was not excessively hot out. The power steering pump also became quite noisy toward the end of the trips (again - both ways). I don't think that these two noises are related. Being new to the truck, I am not sure what noises are normal. Thanks for any insights you might have to offer.

Actually they are related. My break booster had to be replace on my new truck already. It uses the pressure from the power steering pump to give you the break pressure.

Thanks emerick115! It looks like my first trip back to the dealer. Hopefully not the first of many trips. What do you think of your Denali headlights? I wanted to do an HID upgrade to my existing lamps. Was the price reasonable? Got pictures?