All explorer's with AT's out there, do you keep overdrive on or off?

[Vozar]

Heres the dilemma. I want my auto tranny to live a good life . I have generally now since i got my 35's and 4.56's kept my OD off. Honestly i like how it drives(engine braking, etc. Is it really better for your tranny to keep OD on or off. I have the gears now so it takes alot of stress of it. Im still not sure whether to keep it in OD or not. when i get above 45 and am at a constant speed i will always keep it on because i am in the top of 4th if i dont. Any tranny experts out there?. I would value your opinion.? Thanks , Matt

 

[sunbum]

Good question... mine's always on but I guess I'm hurting myself slightly off the line, eh?
If not on, unless you're maintaining above 45 or a stable speed, does it negatively impact your gas mileage?
Inquiring minds want to know.

 

[Alec]

Overdrive is just 4th gear in the A4LD or 4R55E or 4R70W, and 5th in the 5R55E. All you're doing is limiting the tranny to it's gear selection. Nothing more, nothing less.

 

[Fairlane390]

When in OD, will the trans shift a total of 3 times, that u can feel? Also at what speed or rpm does the trans go into OD? Just purchased a 92 Explorer, all new to me.
Thanks,
Great web site.

 

[Fish Man]

the tranny will go into OD whenever you let it. it is different every time depending on how you are driving, where you are driving, etc

 

[Mike_H]

Originally posted by Fairlane390
When in OD, will the trans shift a total of 3 times, that u can feel? Also at what speed or rpm does the trans go into OD? Just purchased a 92 Explorer, all new to me.
Thanks,
Great web site.

Most of us first gen X drivers keep it in D untill we hit highway speeds. The tranny does not hold up to well if you drive around in OD the whole time.

 

[88vert]

Originally posted by Mike_H
Most of us first gen X drivers keep it in D untill we hit highway speeds. The tranny does not hold up to well if you drive around in OD the whole time.

Same here

 

[Alec]

By definition, an overdrive has a faster output speed than input speed. It's a speed increase -- the opposite of a reduction. In this transmission, engaging the overdrive accomplishes two things at once. If you read How Torque Converters Work, you learned about lockup torque converters. In order to improve efficiency, some cars have a mechanism that locks up the torque converter so that the output of the engine goes straight to the transmission.

In this transmission, when overdrive is engaged, a shaft that is attached to the housing of the torque converter (which is bolted to the flywheel of the engine) is connected by clutch to the planet carrier. The small sun gear freewheels, and the larger sun gear is held by the overdrive band. Nothing is connected to the turbine; the only input comes from the converter housing. Let's go back to our chart again, this time with the planet carrier for input, the sun gear fixed and the ring gear for output.

Ratio = 1 / (1 + S/R) = 1 / ( 1 + 36/72) = 0.67:1

So the output spins once for every two-thirds of a rotation of the engine. If the engine is turning at 2000 rotations per minute (RPM), the output speed is 3000 RPM. This allows cars to drive at freeway speed while the engine speed stays nice and slow.

Because of this gear reduction, this puts more stress on the tranny (torque) than 1:1 and above gears.

 

[mrboyle]

It is always better on the tranny to keep it out of OD unless you are maintaining a constant speed above 45mph. The tranny will shift into OD at speeds as slow as 35mph. This is way to slow of a speed and will lug the engine and create a serious load on the tranny. Over time this will shorten the life of the tranny.

 

[Billy177]

for those of you who didn't know i the 5R55E maby others od off offers engine braking in 3rd and 4th gear and also reverse(i think) read a while back in the ford service cd

 

[dan leon]

I have a 96 xlt v6 with 3.73 and 30's. I always have left it in OD. In the past, I have tried to select D but I forget alot. Oh well, I guess would rather waste a transmission instead of spinning my motor faster and wearing it out sooner.