Forum Discussion

Redram99's avatar
Redram99
Explorer
Feb 14, 2018

Overdrive lockout on ford e450

Does anyone know if it’s possible to wire in a switch to lockout overdrive?

It would be great to be able to drop the tranny to drive in advance of a hill. I feel it would put off shifting to 3rd significantly.

This would make cruise control much more useable.

I have already installed five stars tuning which made a night and day difference.

Thanks.

19 Replies

  • My biggest disappointment with the Ford 5 speed was the inability to lock out 5th. Sucks in the hills. 5 Star are the people you want to call and ask.

    AFAIK there is no unused input available to the transmission control that would enable that. I'm pretty sure you could ask 5 Star to give you a program that would lock out 5th using Tow/Haul, simply by raising the 4-5 shift to some very high speed you wouldn't reach. Effectively giving you just 1-4 when T/H is enabled.
  • Our 2016 is on the E-450 chassis with the 6 spd tranny. Towing a JKU as a dinghy we always use the tow/haul; unlike our 2008 RAM this doesn't disable the over drive. There is no OD off either like the RAM has. Typical of FORD to be behind the others.
    When it's in the budget I'll be looking into the 5 stars as the shift patterns are all wrong on the 6 speed. Would also like to disable OD at times.
  • Older Fords (with the 4R100 transmission) had a plain overdrive off where the tow/haul button now is. It did exactly what it was advertised as doing: locked out overdrive, but didn't alter the shift points in any other way.

    Tow/haul is much smarter overall; it does not disable overdrive, but does change the shift points around and enables some automatic engine braking by downshifting under certain conditions when the brakes are applied and also tinkers with some of the internal shift timing and programming to reduce excess heat buildup etc. (adjusting things like when the torque converter locks up).

    If you really want it to downshift earlier, probably the best method is to tap the gas as you approach a hill on cruise to force a downshift. I'm not sure you'll find much difference in shifting down to third, though; my hunch is that it may actually not be shifting down to third, in most cases, though I obviously am not riding along in your RV and may be entirely wrong. I do know that my 4R100 rarely if ever shifts down to second on the highway. (Second, third, and fourth on the 4R100 are identical ratios to third, fourth, and fifth on the five speed transmissions. The extra gear was added between first and second on the four speed.)
  • My e450 is a 2010. The button on the gear shift is for tow haul only.

    It does not disable overdrive. On most fords you can disable OD but not these.

    I thought I had seen a fix for this.
  • Tvov's avatar
    Tvov
    Explorer II
    What year is the vehicle? With my 2008 F250, the tow/haul does not "lock out" overdrive, it delays shifting into it until you are cruising on flat roads. My truck has the 5 speed torque-shift transmission.
  • jerseyjim wrote:

    Just push the button located at the end of the gearshift selector.

    Little light comes on says "off".(Overdrive is now turned off)

    Why you would want to do this permanently...I don't understand. On a flat road, take advantage of the lower RPMs, especially in CruseControl.


    Yup! that's what the tow mode button is for! :B
    Push a button and overdrive is off.
  • If you're driving on a lot of hills, I'd suggest turning off the cruise control and engaging the tow/haul feature, if not already in use. I believe it's a good idea, to always have tow/haul turned on.
  • JaxDad's avatar
    JaxDad
    Explorer III
    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.
  • Just push the button located at the end of the gearshift selector. Little light comes on says "off".(Overdrive is now turned off)

    Why you would want to do this permanently...I don't understand. On a flat road, take advantage of the lower RPMs, especially in CruseControl.