This may be common knowledge for many of you, but for those that haven't heard this before - do not use your exhaust brake on slick roads! I was towing our horse trailer with our 3500 dually late last week - roads were dry but it had snowed a little the night before and we had maybe 6"+ on the sides of the roads from previous snow storms. The sun was out but it was cold (25 degrees or so) and very windy. Came upon a place where the wind had blown snow across the road - maybe a 1/4 mile section on a slight decline. The wind, sun and cold temps combined to make it ice underneath with a thin layer of snow over it. I saw it ahead of time, slowed down to about 25mph-35mph and punched the 4 wheel drive before hitting it, however, I did not turn off the exhaust brake. Got maybe a hundred yards or so into it and as the exhaust brake did its thing, the back end of the truck broke loose to the right and the trailer started coming around. I stayed off the brakes and used a bunch of little inputs to the wheel to keep it as straight as possible as we had no real traction, but by this point was sideways across part of both lanes (2 lane road). Fortunately, I was able to keep the trailer (gooseneck) from coming around and after some slipping and sliding, and a whole lot puckering, straigthend back out and made it back to dry pavement. Fortunately, it wasn't a super whippy slip and slide as my speed was relatively slow, so the horse was fine, as were my wife and I and all equipment. I'm not sure I would have been able to save a bumper pull as they rotate around faster than the gooseneck and I figure the weight of the gooseneck on the bed probably helped a little bit to regain some traction. Anyway, lesson learned on the exhaust brake and slick roads. Be careful out there!