Overdrive lockout on ford e450

I drive our 2005 E450 with it's 5-speed (6 gear ratios internally - with computer selection between two of them) Class C almost full time now with Tow/Haul mode engaged. Overdrive and cruise control still work in Tow/Haul mode and of course downhill automatic down-shifting happens all the time when in Tow/Haul mode whether in cruise control or not.

I find staying in Tow/Haul mode improves overall response and driveabilty under all conditions. However, this may be due to our Class C being relatively low in weight (24 feet @ ~11,800 lbs.) and built on the E450 chassis with it's low 4:56 rear differential ratio.

I believe on the 5 speed f series transmissions, you can lock out overdrive with the tow haul button. Quick press of the button engages townhaul, and a long press of the same button disables overdrive.

Would be real nice to have on the motor home.

Btw- 5 stars tuning is the best thing that ever happened to my motor home


Unreal how much better the drivability is!!!

X2 - Get 5-star tuned. It won't be as shifty to start with, and they can include an O/D lockout tune.

JaxDad wrote:
Keep in mind that once the TX drops out of overdrive the converter lockup releases also, when that happens the slippage creates a lot of heat fast.

Unless you have a TX fluid temperature gauge you could very quickly get above the critical temperature of 225 deg. F.

Bad things happen very quickly after that.

The torque converter will still lock, regardless of the overdrive selection.

Redram99 wrote:
I believe on the 5 speed f series transmissions, you can lock out overdrive with the tow haul button. Quick press of the button engages townhaul, and a long press of the same button disables overdrive.

Would be real nice to have on the motor home.

Are there certain years for that? I'm off to check my owner's manual!

Home Skillet wrote:

JaxDad wrote:
Keep in mind that once the TX drops out of overdrive the converter lockup releases also, when that happens the slippage creates a lot of heat fast.

Unless you have a TX fluid temperature gauge you could very quickly get above the critical temperature of 225 deg. F.

Bad things happen very quickly after that.

The torque converter will still lock, regardless of the overdrive selection.

This is true. Even on my lowly 4R100, the torque converter locks up in third gear after maybe half a second, and so far as I can suss out will also lock up in second gear if appropriate. I don't think I've ever cruised in first long enough to find out if it locks up there or not.

Newer transmissions are generally more likely to lock up the torque converter than older ones so as to meet fuel mileage goals for the vehicle makers.

Heard from 5star today. Apparently they can program a tune to lockout overdrive.

I am hoping they can calibrate a tune that only uses 4th while I activate tow haul. That way when about to pull a hill or need to slow down slightly I can click towhaul and automatically drop to fourth. Once things level out again, I can disable towhaul and back off to the races with overdrive.

Redram99 wrote:
Heard from 5star today. Apparently they can program a tune to lockout overdrive.

I am hoping they can calibrate a tune that only uses 4th while I activate tow haul. That way when about to pull a hill or need to slow down slightly I can click towhaul and automatically drop to fourth. Once things level out again, I can disable towhaul and back off to the races with overdrive.

That is the way tow/haul works on my 5 speed trans in my F250 from the factory. If the truck needs the power, the trans quickly downshifts as needed, but hit a flat spot it shifts into overdrive.