Got a '07 with 4.0 engine. I've been towing a 16' aluminum Seaark with 40hp Evinrude. Boat, motor and trailer probably weighs less than 2200#. While towing the olny time it shifts out of overdrive is up long hills or getting on the express way.

i'm running about 2000rpm in overdrive but if I run without it I run about 2600rpm.

Should I tow in OD or not?

 

I think it'll be fine. If you have enough weight where it shifts in and out of OD a lot I'd run it turned off but with the fairly light boat you're dragging around I wouldn't worry about it.

 

I tow a 17ft stratos with a yamaha 50, close to the same weight as yours maybe a little more. I always turn OD Off. Better safe than sorry, towing a boat isnt the time to worry about a few mpg.

 

The truck will down shift when it needs to. If you need the power just step on the skinny pedal and it will always downshift.

Only time I drop out of OD is when I climb long hills and know OD isn't an option.

 

Do NOT tow in OD.

 

If it weighs less than 2200# I wouldn't worry about it. If you get into hilly terrain I would keep it out of overdrive. I had an automatic that I towed with regularly and more then 2500# without any issues.

 

You'll have to go by feel. It also depends on how fast you want to go. If you don't mind not using the cruise control, and letting the truck decide what speed you're going up hills, then OD on is fine. If you wanna set the cruise and not worry, it will probably force a lot of shifts, which isn't good, so then you should lock it out.

You can kind of learn the spot on the pedal where the downshift will occur, and you can just hold the gas right above it to avoid the downshift when you hit grades.

 

...From the Ford guide to towing....

DRIVING WITH AN AUTOMATIC
OVERDRIVE TRANSMISSION
With certain automatic overdrive transmissions,
towing – especially in hilly areas – may cause
excessive shifting between overdrive and the next
lower gear.
• To eliminate this condition and achieve steadier
performance, overdrive can be locked out (see
vehicle Owner Guide)
• If excessive shifting does not occur, use overdrive
to optimize fuel economy
• Overdrive may also be locked out to obtain engine
braking on downgrades

Good info for all things towing with a Ranger
http://www.ford.com/assets/pdf/towin...ANGERsep09.pdf

http://www.ford.com/towingguides/

 

i tow a 16 ft fiberglass bass boat with a 50hp evinrude, i have a 4.0 and 4.10s. only time i keep it out of over drive is on back roads. i can use cruise control on the interstate 70-75 mph it will not down shift. its all about knowing your truck and where the sweet spots are.