How strong is OD in the 4R70W

[wpurple]

Was reading an article that the reason why you shouldn't tow in OD is not so much because of overheating the fluid, but straining and eventially failure of the OD clutch pack. I tow in OD as much as I can when when terrain permits, and it runs about 20 deg cooler, but now I am wondering whether I should run in 3rd, 20 degrees hotter to eleviate blowing out the OD clutch pack???
I am towing a 4500# camper. I always shift out of OD before the TC unlocks.

Comments?

BTW 99 Mounty 5L

 

[Skibug]

Get a good tranny cooler and keep it out of overdrive. I tow my 2900 lbs boat with my 4.0 all over even on some 300+ mile trips out of overdrive. OD is just not meant to tow. I know it is a gas hog that way, but I would like to pay a little bit more in gas than my tranny have problems. If the 20 degrees hotter out of OD is still within the safe limits of the ATF fluid, keep it out of OD. Just my oponion.

 

[wpurple]

I added an additional cooler along with the factory one and went with Royal Purple synthetic.
You would think that if the OD clutch pack was slipping you would see it in the temp???

 

[V8BoatBuilder]

Subscribing..... interested to find out if its better to tow in OD with cooler temps, or 3rd with warmer....

 

[slag]

its a pretty tough tranny. Its stock in many 97+ F150 trucks and can take a fair amount of abuse.

That being said, if you are climbing hills, turn od off.

If its relatively flat (i.e, Kansas), i think towing in OD would be fine as long as your engine isn't downshifting a lot.

 

[wpurple]

You say it is stock in the F150's but I wouldn't consider it a real work horse and the F250's have the 4R100W.

 

[RiverRat]

You can get a 4R70W behind a 5.4 and that engine puts out a lot more torque that the 5.0. I tow in O/D as much as possible. If the tranny it kickin' down due to terrain then I'll shut it off. You just gotta get a feel for when to and not to use o/d.

What kind of tranny temps do you encounter?

 

[slag]

You say it is stock in the F150's but I wouldn't consider it a real work horse and the F250's have the 4R100W.

No one is saying its a real work horse. The F150 is only a 1/2 ton truck, not a heavy duty truck by any means.

I also have the 4r100 in my F150 with the 5.4 liter, but the 4r70w is very very common in the F150 with towing capability into the 7-8k pound range.

 

[wpurple]

I wasn't trying to imply that anyone was saying a F150 was a workhorse, just trying to put the strength of the 4R70W in perspective.