Awesome. I was gonna tell a similar story about my old '84 Z28. I could wrench that rear hatch open no matter how frozen the doors were. Was a little tough opening the T-tops to climb back out to close the hatch, then back through them to get driving.
Wasn't too cold holding the T-top partially...
I think adding bigger tires and armor from the ranger up to the tremor demonstrates that their may be a large penalty. As in 5 MPG on the highway. That's over a 20% loss.
Yes there is regearing and possibly less of an engine strain with the 2.7, but still. The data is there, on a ford vehicle...