My only experience was towing this 2800 lb. 6x14 in Colorado with a 3.5 Ecoboost with 3.55 axle. No sweat whatsoever pulling it all over the San Juan Mountains. 16 mpg too! 4600 mile round trip from Georgia, including 1400 miles in the CO mountains.
The hp loss at altitude is the reason I and most other high elevation dirt bike riders prefer 450cc and larger engines. We ride over some 13,000 ft. elevation passes. There the power is down 39% from sea level. My bike is 510cc, so it performs as a 311cc engine would at sea level. Too bad there are no Ecoboost dirt bikes.
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