I just read in another thread that it's OK to keep my tranny in OD when towing @ 12,000 lbs.

My truck has a 6" lift and 37" tires. (I did not modify anything except suspension and steering stabilizer.) I have been advised by several reliable sources NOT to tow in OD.

Which is it??? Use OD or NOT to use OD? That is the question.

 

1) If your tranny is hunting between 3rd and 4th, turn OD off.

2) If you have a tranny temp gauge that gives you actual temp (not the stock idiot gauge in the dash), you can watch temps and turn OD off if it starts to climb.

3) Going down grade at highway speed, turning OD off will give you a little help holding back the train.

4) Approaching an upgrade, turn OD off before you start to lose speed (downshift before the truck would on its own).

5) With your 37's, you will probably lock out OD more often than with stock tires.

 

Patrick, if what you are pulling is what is in your picture then you should almost never have to switch the OD off. You should be able to drive down the road with that camper at 65-70 mph and pulling 2100 rpms.

From reading your post in the other thread (you should pull it over here) it sounds like you already have some major problems going on with your tranny and you should be saving your pennies, because a replacement or over haul looks to be in your future. If you have to 'pull over and stop' and let your tranny temps come down a couple of different times..... putting the OD on or off is way pasted the conversation.

Nice looking truck.

 

Thanks. I appreciate your insights.

Fortunately, my tranny doesn't hunt between 3rd and 4th. but I've always just played it "better safe than sorry" and have kept it out of OD. If i'm hauling on pretty level grades, I may let it run in OD from now on.

I like the sound of a custom temp guage for the tranny. Is there a good one out there?

 

Thanks for your insights and concern.

Yes, four years ago, my tranny started to get hot. It was on a 101 degree day pulling 12000 lbs up some steep TN mountains, stuck behind a moron poking along (who was disrupting air flow) while I kept it in 2nd gear. It happened only that one day. I've kept a very close eye on it, and it hasn't happened since.

I remain convinced it had to do with the fact I kept it in 2nd gear.

 

+1 on the trans temp gauge,its a must. Also keep in mind the stock trans cooler on our trucks is junk,get a trans cooler from a 6.0 equipped truck and your cooling issues will be non existent,especially since you said your trans doesn't shift in and out of gear...JMHO..Phil

 

I pull a 32' fiver and used to pull a 36' jayco (heavy, but never scaled it). I have never locked out OD. There have been a few occasions where I wanted to command a shift down without adding throttle and I used the button, but not because I was searching for gears, it was just easier to push the button.

There are a lot of rolling hills along the interstate here, and we go up to Alabama and Georgia a lot too. With my Php tunes I can accelerate heavy grades in OD if I'm already close to 70. 65 and below the truck commands a down shift, but I've never had it search for the right gear since I've had tunes. Before it would down shift on every grade to maintain speed and that's not desirable.

 

Was it your engine or your transmission that was getting hot? How do you know how high your tranny was without a guage? Putting it in 2nd would raise your rpms up when going so slow up a grade. Your OD would not (should not) come into play with that going on. Nice and steady pulling up a grade (even behind a moron) the temps (engine) should not go way high. Is it time for a coolant flush and a clean air filter (bigger air filter?).

 

Has your transmission ever had a fluid and filter change? You can do it your self.


https://www.ford-trucks.com/forums/1...questions.html

 

Here's another thread with pics and a video. You want the deep pan filter btw.

https://www.ford-trucks.com/forums/1...and-video.html