I have a 2003 f-250 ext.cab v-10 3.73 gears with 40000 miles also have a 2009 sundance 3300sk dry weight 10000 fifth wheel, is this truck setup safe to pull from kansas into the rockies (salida) it pulls fine around here just woundering if it will pull in the mountains if any one has a similar vehicle or pulls in the mountains please respond!

 

It'll be fine. Don't worry about it when it shifts into 1st gear and screams when going up extreme grades, the V10 is designed to rev, you won't blow it up. Get a trans temp gage and monitor it when going uphill, the coolers on these transmissions aren't that great. A good precaution to take is to get a trans cooler for a 6.0L diesel truck. They are significantly bigger.