Towing in overdrive or pushing the O/D button in

Thanks people, makes sense to me...Excellent article from Lawtonglenn,
I'll be heading out with the button in or "on".

Here's a REALLY good explanation of the difference between the O/D off and Tow/Haul buttons on Fords

Here's a REALLY good explanation

RoyB wrote:
I will push my O/D ON when on level highway and do steady driving but when I start getting into the hills I will switch it off...

I'm guessing that is the O/D button... It says TOW on the instrument panel when pushed in...

In my Chevy truck, the TOW button changes the shift points of transmission, but does not directly turn the OD on and off. I need to do that by moving the column shifter from D to 3.

Eric

My 1997 Ford owner's manual says to turn off the overdrive while going up or down steep hills. My 2013 owner's manual says to use the tow/haul mode when towing. My mechanic who was a service manager for a Ford heavy duty truck dealer says don't tow in overdrive.

Agree, best MPG is at lower engine RPM'S. But, if the transmission is "hunting" between gears, select the lower gear.

BUT, that advice goes for ANY transmission, any vehicle.

If anyone needs clarification on what hunting is, let us know-- as it can really hurt a transmission.

Chopperbob wrote:
Sorry for the off post but does your trans fluid go through the radiator?
I bypassed mine. Works great over 100,000 mi like that.

Yes. I would not recommend removing the radiator from the loop. It provides much of the system heat rejection capacity. The only benefit I could see is if the radiator were undersized, which is not the case with the V10.

Sorry for the off post but does your trans fluid go through the radiator?
I bypassed mine. Works great over 100,000 mi like that.

j-d wrote:
Bryan, Do you run an aux trans cooler? Trans temp gauge?

I replaced the stock AUX trans cooler with a larger Tru-Cool max 40,000 GVW cooler. This was necessary because the deer-guard and center lights blocked enough airflow the stock cooler was no longer adequate. Prior to those upgrades, the stock cooler was sufficient. I have a Banks trans temp gauge mounted on the A-piller.

Note: the highest trans temps are usually right after leaving the freeway, especially if I exit into a hilly area like most of the Portland area. Cruising on the freeway temps are never a problem. The only highway trans temps really got hot was coming west-bound out of death valley. I was right at 22k combined, and it was 107F out. I ended up pulling over because my rear diff temp gauge maxed out at 250F. Trans temp was getting high too and probably would have hit the yellow zone soon if I hadn't pull over to let the diff cool.

x2 on Bryan's eloquent statement!

Bryan, Do you run an aux trans cooler? Trans temp gauge?

The only time you need to turn off Overdrive is if the transmission is "hunting", meaning it is frequently shifting between drive and overdrive. The only other time is when you want to use the engine for braking.

I tow nearly 100% of the time in OD, and my combined weight is usually around 22,000 pounds and can top 25,000 on occasion. I have 358,000 miles on my transmission.