"Tow/haul" question

[BHowell]

I've been towing my RV(7000# Airstream) for about 3 months now with my new truck and can honestly say I cannot tell the difference between using the "tow/haul" feature on my auto transmission and not. The shift pattern seems the same either way. Is there a way to positively check to see if the "tow/haul" feature is working?

Thanks

 

[Rider]

Is there a way to positively check to see if the "tow/haul" feature is working?

Engage T/H mode. Descend really steep grade without a load or mild grade with one--the idea is that the truck will speed up from gravity, unaided by throttle application. It should hold a gear (instead of upshifting) unless you add throttle, at which time it will upshift. Heck, you can even try it just on any ol' exit ramp. It'll downshift as you brake.



That's the easy way to tell if mine is in T/H mode, anyway.