yep ive never turned the o/d on since i bought the truck. i always shut it off. with 265's it turned 3000rpm at 70 with 285's it turns 2750 about....theres nothing wrong with those rpms and the powerband of the motor...you get scared when the rpms are that high? i get scared when i think about pulling all that at 1900 rpm.

 

I do not mean to be rude; but I really don't agree with the advice I am getting. I think it's insane to travel on the highway at 65mph for 3 hours straight, with overdrive off. To me, I think you need to feel the truck out. If it isn't hunting for gears, I think it's quite fine towing in overdrive on the highway. If I'm in the city, it's a no brainer, I always turn o/d off, because I don't need to go over 50mph. Now obviously if I'm on the highway and the truck starts to loose steam, or if I'm approaching a giant hill, I'm going to pop it out of overdrive before it starts trying to hunt for gears. But I cannot say I agree that one must completely turn overdrive off the entire way, especially on the highway. If the truck is moving right along and it isn't having a difficult time sustaining highway speeds, I think it's appropriate to leave o/d in. Again, if I was in the city hauling a trailer or doing a home depot run, I have always turned o/d off; but this is a three hour highway trip.

 

This is what I would do 65 od on on the flats 65 off before you hit the hills. And when You hit the back roads leave the od off. Or just burn up another tranny your choice. Where only trying to help. I know when I go to the ponocos I turn the od off when i get off the highway. But if there is a flat part in the road I put the od back on. Thats when i'm not towing. Hope to get up there next weekend but should really go to work.

 

And you wonder why you burnt your tranny up. These 46re trannies are not bullet proof.
I am not being rude, but rather just calling it like I see it.

 

My other transmission burnt up because it had 35" tires with 100,000 miles on it from a previously abusive owner. The only thing I'm disagreeing with is guys saying to leave o/d off the entire time on the highway. I don't appreciate guys insinuating I don't know how to maintain a vehicle. I take especially great pride in maintaining my truck in all aspects. I'm leaving tonight at around 9pm when I get out of work. Should be up there at around midnight if things go well. Already have the snowmobiles, trailer, and gear ready to go. This is going to be a special time. It's just going to be me, my twin brother, and my dad enjoying some riding in thick snow up at our grandparents. They have acres upon acres of gravel pits and blueberry fields to ride on, along with many other adjacent trails along the way.

 

65 mph I would turn it off unless your going up alot of hill. 55 I would leave it on. Whats is the weight of all of the stuff your draging up the hill.

 

What I am getting at is, there are a bunch of people on here who have burnt their tranny up doing exactly what you are thinking about doing.
Hell I burnt mine up at 70,000 with 2,500 pounds in the bed. I never even thought about o/d on the drive home. About ten miles from home it started slipping like hell, and with in the week it was in the shop getting rebuilt.
I learned my lesson the hard way. Now, when I ever get anything in the bed or on the hitch o/d is OFF.
BTW: towing at 75 is sucidal. I have done it, but that was in an F-350 Dually powerstroke. Even then I didnt trust it.

 

I honestly think you're probably fine leaving it in OD on the flats going about 65. But if there's any relief to the landscape at all, just turn it off until it flattens out. That way you don't have to be constantly vigilant for every little hill and can kick back and enjoy the ride.

Personally, I would just leave OD off, but it's your truck, and at the end of the day it's your decision. Just expect to get flamed (not by me) if you end up with problems after the trip.

 

Yep it's your decision like said above and you get to do what you want but if it was me I'd turn OD off. The manual says too. Almost anyone I know that tows much at all says to. Others have tried it and burnt up their transmissions by not taking it out of OD. To me just too much of a risk so that you can make it there a few mintues faster or save a few dollars in gas. Unless you have a built transmission I wouldn't town in OD and since you have a stock one now I'm not sure it's the best idea.

Have fun on your trip though.

Have you ever towed something going 75? It's not a good idea. It takes a lot longer to stop with a trailer than without so if you ever have to stop quickly you can forget about stopping. It's also more of a problem if the trailer gets to swaying or anything like that. Not saying it can't be done just saying it's probably not the best idea.

 

Wish ya luck. oh, and have fun in the snow without your limited slip now