overdrive function

Can anybody tell me when do i need to turn the overdrive off and on?and how much speed is allowed when overdrive is engaged.i understand turning overdrive off will lengthen the life of transmission.Thanks!

Overdrive by default is on. This means that the vehicle is allowed to shift into its highest gear (overdrive) to have a lower engine speed while cruising.

Turning overdrive off will keep it from accessing the higher gear and thus keep the transmission from constantly changing gears. (For example, when pulling a heavy load up hill.)

The only time I ever use it is when towing. Speed with overdrive off is the maximum speed of which whatever gear its in, but it's not recommended to drive fast and pull a heavy load.

Does anyone else (besides me) turn the O/D Off when taking a curve at above 50mph to get a better hold of the engine and traction? It feels like lowering gear on a manual ****** vehicle, instead of going in a curve at 4th gear, you would lower it to 3rd (what I would do) and lightly tap on the gas.

thanks BMR!does speeding up to pass another vehicle putting more pressure on transmission and eventually lead to transmission failure?sorry for asking this questions.ive only had my liberty for a year and never bothered to find out all of its functions.

overdrive

which is better?turning off the overdrive on a regular driving?when do i turn overdrive?is it when the vehicle is in idle?

I'm pretty sure that the problem is mostly with too much heat when towing due to excessive up/downshifting because it can't hold it's speed with the extra weight.

So like basically if you were towing up a hill the trans would downshift, once speed is reached, it would then upshift to OD gear, but then quickly lose speed again and downshift.

Someone else with more knowledge should chime in if they know more details...

EDIT:

jeff said:

which is better?turning off the overdrive on a regular driving?when do i turn overdrive?is it when the vehicle is in idle?

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For regular driving it should be off. MPGs will be better because the trans can access the OD gear.

hyedipin said:

Does anyone else (besides me) turn the O/D Off when taking a curve at above 50mph to get a better hold of the engine and traction? It feels like lowering gear on a manual ****** vehicle, instead of going in a curve at 4th gear, you would lower it to 3rd (what I would do) and lightly tap on the gas.

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yes i do or else i get the rumble strip sound. if it ever gets below 55 unless on level road or downhill, i always do this until my speed hits 60 again.

i use it as if it were a manual and just think of it as 4th gear rather than OD, because thats all it is anyway.

all i worry about is, how many times can one use the OD button on the shifter before that button wears out?

I don't think the button will wear out. It is just a press button and not a switch. Just touch it lightly to turn on/off. Switching is done by the computer. Hence the delay in O/D OFF light in the dash.

I always leave it in the O/D setting except.....

1) When towing. It keeps you up in your engine rpm power band and keeps the ****** running cooler under load.

2) Hilly terrain when the ****** hunts for gears. Locking out O/D keeps your rpm's in the motor's power band for climbing hills easier and keeping the ****** cooler and gives you engine braking going down hill.

3) sometimes in a 45 speed zone. My ****** shifts into O/D at around that speed so if I am going that speed and it starts hunting I just hit the button so it won't go to O/D until I can get my speed up to 50 where it won't hunt for gears.

4) when it is very cold out I will lock out O/D for a mile or so and by then I am in a 55 speed zone and let it go to O/D. I just want it to warm up a little.

The only thing that is bad for an A/T is when it continually hunts for gears and then it gets real hot......too much heat is bad. It might be an A/T but it still has to be shifted under certain road and speed conditions sometimes.

You will feel when it needs to be shifted between O/D and D.

Everyone drives different. If you have a heavy foot at the wrong speeds (especially at the shift points of the ******) and let it continually shift back and forth between D and O/D you are heating it up unnecessarily and abusing it and asking for trouble.

Dave

I always leave Over Drive on. Unless I'm going down a huge hill b/c then i'll use the engine to help keep my speed down when coasting.

My parents bought a used vehicle in which the previous owner never used over drive (which they didn't know at the time) and b/c of that the entire engine and ****** had to be rebuilt b/c a lot of parts were warped from heat of running at high speeds while in only Drive.

So in my opinion. If the vehicle has over drive. Leave it on over drive. Unless there is a good reason to turn off.

ChiefRudy said:

I always leave Over Drive on. Unless I'm going down a huge hill b/c then i'll use the engine to help keep my speed down when coasting.

My parents bought a used vehicle in which the previous owner never used over drive (which they didn't know at the time) and b/c of that the entire engine and ****** had to be rebuilt b/c a lot of parts were warped from heat of running at high speeds while in only Drive.

So in my opinion. If the vehicle has over drive. Leave it on over drive. Unless there is a good reason to turn off.

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I agree with Chief Rudy, the over drive option should be left on all the time, except on the odd occassion. I too only turn the over drive off when I have driving down a steep winding hill. I have always condsidered turning over drive off like driving an automatic in third gear. Its ok at low speeds only.

I turn O/D off when going up hills mostly. You can leave it off for as long as you want, it will not effect the transmission, just higher RPMS and more gas consumption. With O/D on, it shifts to 4th, then the converter locks-up at too low a speed for me, so I use it off and on all the time. In racing conditions, I have it off till I am ready for 4th. Did with my Avenger too. 145K miles on that, all original drive-train, no replacements, and those Ultradrive transmissions were WORSE than these ones...

hyedipin said:

Does anyone else (besides me) turn the O/D Off when taking a curve at above 50mph to get a better hold of the engine and traction? It feels like lowering gear on a manual ****** vehicle, instead of going in a curve at 4th gear, you would lower it to 3rd (what I would do) and lightly tap on the gas.

Click to expand...

Once in a great while. The KJ has a notorius 'dead spot' (around 40-45mph) in its shift range and if you hover in that speed where the dead spot occurs, sometimes the xmission will go through excessive shifting. I'll sometimes turn OD off when going up hill when I'm hovering in that speed range.

Other times I turn OD off is when I'm off-road.