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-   -   Over Drive Use (http://www.jeepgarage.org/f203/over-drive-use-33331.html)

Amelie 01-01-2012 01:13 AM

Over Drive Use
 
So I know Over Drive is mainly used on the Interstate/Highway and when your above 50 MPH but is it okay to run with Over Drive off while driving on a non-interstate road when going above 50 MPH?

I like to go at brisk pace most of the time and I keep Over Drive off because your speed can fluctuate a lot when not in a highway situation where your speed is mostly constant.

:confused: By doing this does it harm the transmission or anything else? :confused:

DrLocke 01-01-2012 11:26 AM

Re: Over Drive Use
 
I don't think it hurts anything but you mpg. But don't quote me. lol

Amelie 01-01-2012 12:41 PM

Re: Over Drive Use
 
Quote:

Originally Posted by DrLocke (Post 543669)
I don't think it hurts anything but you mpg. But don't quote me. lol

I can dig it lol

cheapjeep 01-01-2012 12:43 PM

Re: Over Drive Use
 
Quote:

Originally Posted by DrLocke (Post 543669)
I don't think it hurts anything but you mpg. But don't quote me. lol

X2

Amelie 01-01-2012 12:45 PM

Re: Over Drive Use
 
Quote:

Originally Posted by cheapjeep (Post 543693)
X2

That's good to know. My sister always tries to tell me that I'm going to wear the transmission out. lol

misfit77 01-01-2012 12:56 PM

Re: Over Drive Use
 
I swear I get better MPG if I stay out of OD unless my tach goes over 2K RPM. It might be due to the Sahara wheels I have.

01grand 01-01-2012 01:48 PM

Re: Over Drive Use
 
It could actually help the transmission, less shifting back and forth has to be a good thing I would think. Also I believe a higher gear will also keep the trans temp down as there is less friction from shifting and running a higher gear (making an assumption based on the fact that they tell you to turn off OD for towing/heavy loads)

Amelie 01-01-2012 01:58 PM

Re: Over Drive Use
 
Quote:

Originally Posted by 01grand (Post 543707)
It could actually help the transmission, less shifting back and forth has to be a good thing I would think. Also I believe a higher gear will also keep the trans temp down as there is less friction from shifting and running a higher gear (making an assumption based on the fact that they tell you to turn off OD for towing/heavy loads)

That's interesting; Hey Aaron, how are your Eagle Eye tails holding up? Anymore problems?

01grand 01-01-2012 02:38 PM

Re: Over Drive Use
 
Quote:

Originally Posted by Reichminister Goebbels (Post 543713)
That's interesting; Hey Aaron, how are your Eagle Eye tails holding up? Anymore problems?

They are doing great so far! Not sure if I mentioned this before but the red does flash along with the signals when I hit unlock on the remote. However, they don't flash when just one signal is on. And no problem with any of the LEDs yet, they all still work!

Amelie 01-01-2012 02:43 PM

Re: Over Drive Use
 
Quote:

Originally Posted by 01grand (Post 543733)
They are doing great so far! Not sure if I mentioned this before but the red does flash along with the signals when I hit unlock on the remote. However, they don't flash when just one signal is on. And no problem with any of the LEDs yet, they all still work!

That's good, I was kind of hesitant on buying them since you and several people mentioned they flash like that. Do you have an LED 3rd Brake Light? If so, How's it doing?

You gotta love how ridiculous some sellers on EBay either intentionally or by accident. lol Here's an LED 3rd Brake Light, They have 10 available, each $1000 lol

http://www.ebay.com/itm/99-04-Jeep-G...ht_4547wt_1139

Frango100 01-01-2012 06:46 PM

Re: Over Drive Use
 
On the 42RE tranny, 1st and 2nd gear are underdrive gears ( the tranny input speed is higher then the output speed). 3rd gear is direct drive ( tranny input speed = tranny output speed) 4th gear is overdrive (the tranny input speed is lower then the output speed). With overdrive off, 4th gear is disabled.
Overdrive is there to reduce the fuel consumption and lower the engine noise.
In both 3rd and 4th gear the torque converter will be locked ( a clutch inside the torque converter will be engaged, making the input and output of the converter fixed, to reduce losses inside the converter and reduce significantly the heat buildup).
So it doesn´t matter that much if you use overdrive or not, it will at least not harm your tranny. You could normally expect a higher fuel use when driving at the same speed when in 3rd gear then in 4th, but as misfit77 wrote, for him its the other way around.

JeepMe 01-01-2012 09:04 PM

Re: Over Drive Use
 
Quote:

Originally Posted by Frango100 (Post 543821)
In both 3rd and 4th gear the torque converter will be locked ( a clutch inside the torque converter will be engaged, making the input and output of the converter fixed, to reduce losses inside the converter and reduce significantly the heat buildup).

The only time it will lock up in 3rd gear is when O/D is off. If driving in normally, it won't lock up until you get into 4th gear.


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