Towing with my ford F150 2004 auto trans, 4.6 motor 3.55 rear end.
I have been told by a friend that you should never tow anything in OD. You should always have your OD off when you are towing anything. The low RPMS generated by towing in OD are not good for your transmission and can damage your OD gear (Transmission).

I thought if the transmission is shifting excessively (frequently kicking down to maintain the speed) that is when you should turn the OD off.

For low RPM I am talking about 2k or under that. TIA

Bro

 

Whenever I am towing anything I try and keep the O/D off for any climbs or through towns and citys and stuff like that. But when I'm on the highway and I hit the speed I want I usually put the O/D back on, keep RPMs down and keep fuel mileage reasonable.

 

Anything heavy or questionable I take OD off. If it is something light I will keep it in OD until it starts shifting frequently. If it shifts in and out of OD a lot then take it out. Never hurts anything to take it out, except fuel economy. If left in, a new transmission might be needed

My brother had a 1994 x-cab z71 and we went down to lake okeechobee fishing and he hauled in OD on the way back and we ended up on the side of I-10 west of Tallahassee with a burned up tranny.

With all of that said, If there is ANY doubt take OD off

 

The story provides no relevance to the situation, even GM guys know the 4L60 is a guaranteed POS.

But i CAN agree with that.

 

[QUOTE=i.ride.suzuki]The story provides no relevance to the situation, even GM guys know the 4L60 is a guaranteed POS.


Actually the relevance was that he hauled in OD and it burned up the transmission.

 

Going by my trusty owners manual, Ford says the only time you need to turn OD off is if the transmission is having a hard time finding the proper gear OR the road has lots of hills. I tow a 6000 lb camper just about every weekend during the summer. When I'm on level, flat road I leave OD on, when I get to some hills I turn it off.

Long story short, don't worry about it the transmission is designed for towing in OD.

 

You can haul in O/D, it makes no difference when your driving down the highway holding a constant speed. Its when your truck is going to be shifting lots that its not wise to stay in O/D

 

Thanks for all of the responses guys, appreciated.

 

The OD towing rule in the owners manual is kind of idiot proof.

You can tow in overdrive if...
1) The truck will stay in OD (not downshift) in slight grades. It's normal for the truck to downshift on steep grades, but you don't want the truck downshifting every 2 minutes.
2) The torque converter clutch stayes locked. Automatic transmissions slip when the TCC is unlocked. That's why you can some to a stop with the vehicle in gear with an automatic transmission. Normally at highway speeds above 35 mph the TCC will lock so there's no slippage, you'll notice the RPM's drop almost like the truck upshifted when this happens. Pay attention to how/when the TCC locks when you're not towing and you'll learn to identify wether or not it's locked. You want to make sure the the TCC is locking when you're towing or you'll burn up the trans. When the TCC is unlocked the trans is generating a lot of extra heat.

 

Also depends on the wieght being towed. For a 4.6 maybe 3-4K is the threshold for turning o/d off, but also looki at the shifting like everyone else said.

On the 5.4 I'd say 4-5K is my threshold for in town and on hwy I look at shifting.

 

If you're close to the threshold, the truck will normally hold OD but not lock the TCC, so just be careful.

 

It depends on the wind resistance the load has , in addition to the weight. I hauled 5500 with my 4.6 with 3.55 gears in OD easily pulling up hills in OD. Was towing a camero on a flatbed double axle steel trailer. Could hardly tell I was towing