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[mack109]

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Basically watch the RPM's and temp gauge while in OD. Dont lug the motor and you will be fine. In mine at 70 MPH with 4.10 gears the engine is screaming when out of OD. Just listen to the motor it will tell you when to shift. Ha Ha [img]/ubbthreads/images/graemlins/laugh.gif[/img]

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I think that AMX 70 is correct. This is exactly what I did last week. I towed about 500 miles with the motorhome and my enclosed race trailer from upstate NY to NH Int'l Speedway (lots of hills). I started out always with the OD switched off and as I gained speed into the cruising range I switched to OD on. As I slowed on the hills I switched the OD off as the engine rpm approached 2000. When I accelerated back up to 3000 rpm I switched the OD on again. This seemed to work very well. I never lugged the motor. I don't have a trans temp guage so I can't comment on the effect on ATF temperature. On the interstate I was maintaining 70 mph and on the secondary roads 60-65 mph. I will continue this practice.

Now I need a trans temp guage. I know that Autometer makes one. Where on the transmission does it get installed?