Automatics, Driving in D

[VeryFast2gDSM]

Whats the difference driving around in OD vs D around town? If driving in D, is it more torquer or is it just in my head?

Ive been driving around in D, and switch on OD when im about 45-50mphs... ### I think my auto picks up quicker from a stop... But is it just in my head?

 

[agedog2gT]

i have an a/t myself, i never use the od, i thought that was for things such as climbing hills or up mountains, correct if im wrong. like i said iv never payed attention to OD.

dropping down past drive there is more tourque but im scared to do that . dont feel right for some reason, did is once and never did it again. feels like to much stress on the motor.

 

[mistagst]

OD in any car is used when you are pulling something or have heavy weight in the car. ex. a truck pulling trailer or carrying furniture. or it is used when you go up a hill. it in a sence "unlocks" some power out of the car, which is why when it is on you use up more gas. it is more of an accelaration booster than anything, it raises your rpm's per gears and gives the engine more room and freedom to accl. next time you are at a light turn it on and give it some gas and see the differance. it shouldnt be used past 50mph tho. puts more strain on engine because it stays at higher rpms. hope this helps

 

[agedog2gT]

there we go, i quote mistagst word for word. thanks bro!

 

[needsy]

WTF!? OD = overdrive. OD on means you have 4 speeds for increased fuel economy. OD off means only 3 speeds so RPMs are higher and more power is available.

Read the wikipedia article: http://en.wikipedia.org/wiki/Overdrive_(mechanics)

 

[mistagst]

oops i said turn on not off ha well you know what i mean

 

[white92talontsi]

Ummm......

Having O/D on or off is not going to make any difference in acceleration in gears before O/D.

 

[VeryFast2gDSM]

Ummm......

Having O/D on or off is not going to make any difference in acceleration in gears before O/D.

Thats what I was looking for... It just seems like car accelerates faster with OD OFF. More torquer... But probably just in my head.

 

[420a-t]

^^^It is all in your head.

 

[GRAVEDIGGER]

This thread is full of bad information. You do not use o/d when going up a hill or towing something heavy. That couldn't be further from the truth. Overdrive is there to bring down the rpm's while cruising (light throttle) to help save gas at higher speeds. As soon as you step on it the o/d will kick out and/or the car will downshift until it reaches the same conditions and goes back into overdrive. With the o/d off you get engine braking similar to a stick shift car when you let off the throttle. That's why when the o/d is off and you step on it the car feels like it has more torque. It's like a stick shift car where 4th gear is direct 1:1 ratio compared to overdrive in 5th gear.

 

[TunaTalon]

In the 2G DSM auto 4th gear is overdrive. Overdrive is good for saving gas while cruising but definitely not for pulling trailers. Overdrive off (3rd gear) on my Talon tops out at 110 MPH and is very handy when the 16 wheeler I'm passing really, really needs my lane.

The added acceleration in lower gears with OD off is not all in your head. The DSM auto tranny has a "fuzzy logic" adaptive shift algorithm that will raise the shift points and downshift quicker when in an aggressive mode. After a 7000 RPM up shift, or enough lateral g force to make your tires happy the tranny will go into a more aggressive mode and stay there until several miles of driving like a blue hair lady. In my Talon leaving OD off (locking out 4th gear) keeps the more aggressive shift mode on while burning more ga$.