over drive on or off?

[grumpyoldgamer]

just a quick question im pulling a 20 foot feather light about 3600 pounds dry and about 4200 loaded i have 07 ST with the v-8 6 speed. should i pull with over drive on or off.
the funny thing is that the truck seems to do just fine with overdrive on
now dosnt the ST have adaptive shifting? (what ever that is) some help in this matter would really be great. we are taking a longer trip in 2 weeks and and its about a 2 hour drive at high way speeds about 60-65 mph. this seems to be the sweet spot with the truck.

 

[edj1993]

I have the exact same powertrain in my 07 and pull a boat about the same weight. You'll get better fuel economy if you allow the truck to decide which gear it wants, and and it will stay in 6th gear much of the time on level roads. It likes to run around 65 mph while pulling. I dont believe you'll cause any problems with the tranny allowing it to jump back and forth between 5th and 6th. When the OD is off, you're actually in 4th gear and will be turning more revs than you really have to.

 

[JohnnyO]

The owners manual will tell you to switch the OD off when towing. That said, what hurts the tranny is when it is constantly shifting between 5th and 6th. If you are on a reasonably level road and it stays in OD then leave it on. If you are going up and down enough or have a headwind and it's shifting a lot, then turn the OD off.

 

[grumpyoldgamer]

well we took the trip and i did a bit of testing on the way with od on and off as i expected the truck did do better with od off. doing around 60 mph rpm's where around 2800 to 3000 so not to bad and we did slightly better on fuel mileage. but anything over 60 the temp starts to creep up and i can hear the fan kick in