Am planning a long haul in the upcoming weeks for an early start on the event season.  I'll be taking just one horse in my 3H GN and it's about 15 hours on the road.  I am quite comfortable driving my truck/trailer the distance, but have never hauled across mountain passes.  Does anyone have any suggestions for hauling over mountains?  Anything I should do before beyond usual trailer/truck maintenance?  Any specific dos or don'ts for the actual drive?  Thanks!

I don't know how steep or long the grades are that you are planning to travel. But I live here in the west and routinely drive over the various summits.  Trappers Loop near my home has a 8% grade that is about 4 miles long.  It's a 50 mph road, But I can go downhill in the proper gear and not use the brakes very much. Same thing with Parleys Summit on I-80 Thats a 20 mile long down hill grade.  The upper portion is a 7% grade.  If I come over the summit at 55mph and downshift a gear, my truck will hold back and stay with in the speed limit (70mph) all the way down the grade.   I might touch my brakes once to slow back down to 55 from 70mph.

I find that I don't have any problems with 12,000 to 14,000lbs of trailer behind my Ford F350 on most of the western hiways using mostly the engine/tranny braking. If the pass you are coming down has a much slower speed limit. ie 25 mph or 35 mph. It will be a different story. The type of truck you drive will also cause some variations of whats easy to do. The 2003-2007 Ford powertrain for example will unlock the torque convertor at 25mph. Which means you have no engine braking at 25 mph or lower. So you would have to use your brakes for all stopping power at these lower speeds. Gas engines have more engine braking than a lot of the diesel engines.  That's why exhaust brakes have been a popular option for diesel engines. ( Dodge even offers exhaust brakes on their Cummings Diesel engines the last year or two). A diesel engine with a properly installed exhaust brake has a LOT of addititional braking. If an exhaust brake is installed it has to have a control module to tel the torque convertor to stay locked up. Most torque convertors unlock when you touch your brakes.

I doubt you will go buy a new truck for the trip. And I doubt you need to consider adding an exhaust brake for one or two trips over a summit. Use caution. make sure your brakes are in good shape before you start the season. slow to reasonible speeds before you start downhill. Down shift and let the engine tranny do as much work as possible and use your brakes when needed. If you are looking at a really steep grade, consider the alternatives that go around it. It might cost you an extra hours drive, but if you are uncomfortable with the hills, that safe decision to make.

All very good advice.  I crossed back and again over loveland pass in Colorado, 12 miles on I think 7 degree grade.  Probably tapped the brakes four or five times.  I kept my 8 wide 10'LQ with 3 animals, loaded with hunting gear.....slow, topped over at 35, started down and kept it in 2nd, turned my flashers on, stayed to the right, and as it would slowly gain speed to 45, would use the brakes to brake back to 35, and it would take a considerable time to get back to 45, whereupon I would brake down again. This method kept me off the brakes as much as possible, with cooling time between applications. 

 There is a little stretch of road just south of Jasper AR, that got our full attention once before the Colorado run, as all our brakes were smokin, no shoulders, deep steep dropoffs, and no runaway ramps!  The difference was, with live animals, that had to be negotiated very slowly on a 2 lane narrow road.  Hopefully your downhill run is not extremely curvy, and there are passing lanes and slow lanes.

The book mentioned above is great, and interesting reading as well.