When i tow my 28" sleekcraft to Lake mead its about a 5 hour drive. and i have a flowmaster exhaust with 3.73 gears so the noise gets kinda anoying all the way there. So when i get to flat groud (when the trans is not shifting) can a turn on the overdrive. Then turn it back off when im slowing down? will driving on level ground for a long period of time damage The trans?

 

I use od when pulling until the trans is shifting down alot to keep the speed I want. When it does that I take it out of od. I have done this on all trucks and the only issue was my 97 chevy could not pull in OD.

 

The only time you should lock out OD is if the trans is constantly hunting between 3rd and 4th gears to prevent overheating, or you'd like some extra engine braking downhill.

OD can pull full load no problem as long as you have the power to hold in the gear.

Adrianspeeder

 

What he said. ^

Only thing is, I watch my tach, as it appears that the torque converter unlocks as step one toward down-shifting to third. If I see this happen, I tap the OD Off button to force the downshift. Maybe I'm being paranoid, but I don't like to see the TC slipping while towing. (Still need to experiment with a TC lockup switch one of these days.)

Andy

 

Last week i pulled a car on the highway with several medium texas hills, and i would shut the AC off for the hills as it down shifted, but left OD engaged for the most part. The engine got a little hot if i left OD locked out.
-Patrick

 

I towed a tandem axle trailer (approx 4000 pounds) from Phoenix, AZ to Austin, TX all with the overdrive on and pulling at about 80-85mph. My truck never even shrugged a bit at it...in fact she chewed it up and spit it out. At the time she was DEAD STOCK...except for the Edge Evo on level 2 & a drop-in K&N. She never got hot in the engine or trans. The engine kept around 196-200 and the trans kept around 168 on the flats and got up to 185 in the big hills.