Can someone tell me if locking out overdrive(pushing the button) changes the gear Ratios or just locks out overdrive. FYI it's a 04 5.4 F150. I know that it's a 4 speed so does that mean it's 3 speeds and 4th is overdrive or is it 4 speeds and overdrive is something else.

I'm so confused

 

When overdrive is off the tranny only operates in gears 1st, 2nd, and 3rd no differently than overdrive is on. Just prevents that shift into 4th.

Putting the shifter in 2 locks in only 2nd and in 1 locks in 1st.

Adrianspeeder

 

Lock out just prevent the OD from operating except it is electrical in control.
The normal high gear is 3rd, a 1 to 1 drive ratio.
This means the engine is driving the wheels thru the rear gear ratio as the only gearing in effect.
Allowing OD to operate take that gear and times it by .70.
Example: Rear gear of 3.55 in 3rd is all there is.
.............Od .70 X 3.55 and you get a final result of 2.485.

This means the engine turns less RPM to go the same speed and distance but it also cuts engine torque hurting throttle response but improving fuel mileage as long as you are light on the throttle.
So the total of gears amounts to a 4 speed.
As a side thought, it can be argued that other resultant ratios can be technically present between 1st and 3rd if one considers the effects on overall gearing when the torque converter is in and out of lock thru-out each gear level, but this is generally never considered in oveall operation.
An example of this is the rise in engine rpm affecting power when the converter is not locked versis when the converter is locked and the engine rpm goes down for the same road speed.
You can drive in 3rd and converter lockup also but this is not a gear change.
The PCM takes care of all this automatically in response to load and throttle operation.
Maybe is corn fused you a little with to much wind!

 

Thanks Adrian and Bluegrass. I think I have a bit better handle on it now.

 

BlackLab, if you were getting confused from the overdrive myths thread, it's because there are 2 types of ODs out there - 1) the transmission OD (the button to turn it off) and 2) an add-on OD, seperate unit that is basically a 2-speed transmission.

The Gear Vendors OD from the other thread is type 2). Not something that many people would ever buy - frankly a light truck would gain little from such a unit.

The other guys hit the nail on the head with the type 1) OD, use it unless you are pulling a load and the trans starts hunting for gears.