Overdrive off or on?

[kjb_r33]

well then, id say you have problems.............

speedo read ok?

[Pva_Glue]

ok so you are saying... put O/D ON when you going over freeway 90km or more...

OFF around town when speed is less than 90Kmph or less...

GOT it

cheers

Joe

[kjb_r33]

Thats it...

Shift point from 3rd to 4th should be 141-151k's full throttle (both power and economy mode)

Around 98-106 half throttle ecomomy mode and 113-121 half throttle power mode..

Obviously no or light throttle the shift speeds will drop somewhat...

These specs are for an r31 but its still the RE4R01A transmission, same as used in the nissan patrols...

May be some slight difference from r31 to r33, but thats controlled by the ECU....

[hippy]

then there must be something wrong .. cause i just went for a drive ... to cruise at 60km/hr with OD off it revs at 2600, with OD on it revs at 1600 ... thats normal right?? so why would i not have the OD on?? you are reving 1000rpm less hence using less feul ... am i doing something wrong here??

[kjb_r33]

Remember i said lower at light or no throttle....

60 ks @1600 is probably about right, but what happens when you touch the throttle, slight incline, wind resistance, passing a car, it drops back to 3rd, right???

And you would probably find that at 60 k's, with overdrive on, its changing up and down ALL the time, not good for transmission, and probably harder on your brakes to.

[hippy]

no i don't notice changing gears much at all ... when i'm cruising at 60 i always go up to 1600rpm ... at it stays there ... with OD on that is ... else it always goes to 2600rpm ... for me i dont' notice changing to lower gears much at all ... i'm not all convinced about what you're saying ... although everyone does seem to agree so i'm probably wrong ... which means everyones driving around 60 at 2600 rpm which seems very high for me ...

[dineth]

ye, in regards to what hippy is saying, im interested to know what all you other Auto R33 drivers rev to when you hit 60 km/h with the OD off. Im the same as hippy. With OD on its about 1600rpm but when OD is off it jumps to about 2600 RPM when hitting the 60 km/h mark. Would appreciate other auto guys confirming this.

Cheers.

[Yotis]

Hrmm.. dunno wat drugs some of these ppl are on, I've never seen anyone drive around town on 3rd gear as the highest gear and only use higher gears on the highway.

The autobox is meant to know which gear is appropriate at wat speed your on (isnt this the whole point of automatic), turnin off OD to save a gear? This is the absolute first time I've read this crap. If you like to only drive with only 3 gears be my guess, me? I would stick with wat the car was originally designed to do that is drive with all gears.

Oh i've never had my gears changed up and down between 3rd n 4th when it is in 4th on an autobox, travelling at 60km/h. Unless of course I plant my foot on 4th gear in which it downsifts to 3rd.

[dineth]

hmm so what ur saying is, its pointless to change between OD on and off regardless of what speed ur going at cos the gearbox will chose the best gear?

im still confused cos while i tend to agree with you, a lot of people in here tend to argue otherwise.

[WazR32GTSt]

what i think a lot of people have said is that 'around town' or in areas of constant changing road conditions (this means traffic lights, hills, dips, braking and accelerating often which generally happens in 60km/h zones) if you have o/d ON, then yes the car will be sitting at 1600rpm. BUT as soon as you accelerate or hit an incline of any sort you will find that the car kicks down to 3rd and once you get up the hill it goes back into o/d. factor in this sort of event happenning 5 times in the space of 5 km and you will have changed gears 10 times. plus driving like this allows the car to run under load in o/d which cannot seem good to the greabox from a logic point of view.

so if we decide to turn o/d OFF, then in the same instance as above there is ZERO gear changes with greabox wear reduced significantly.

so, what is the best thing to do?

some will say drive with o/d on, some with o/d off.

and obviously the correct answer is that its up to you.

I say driving with o/d OFF will cause the trannie to run a tiny bit hotter and also cause worse fuel economy although both will probably be an insignificant amount. Driving with o/d ON is really not for 'around town' conditions, thus why its a button-feature and not a automatic fourth gear.

Just assess the road conditions ahead of you. if there's a flat road for a long stretch then put o/d ON even if you're doing 60km/h. if you're driving in the city/inner suburbs doing 60km/h then leave it OFF to save grearbox wear. in all instances if your speed exceeds 80km/h then i can't justify having the car revving above 3000rpm for an extended period when there's another gear there so always put o/d ON at high speeds.

my 2c anyway

cheers,

Warren.

[WazR32GTSt]

hmm so what ur saying is, its pointless to change between OD on and off regardless of what speed ur going at cos the gearbox will chose the best gear?  

im still confused cos while i tend to agree with you, a lot of people in here tend to argue otherwise.

oh and i tend to think that the gearbox doresn't choose the 'best' gear, rather the gear it has been programmed to choose.

its programming is usually for fuel economy rather than reliability and i find the auto box always chooses the highest gear it can according to the load of the engine. This means that the gearbox will stay under load if it means running lower rpm, rather than changing to a better gear that puts less stress on the engine/gearbox.

[LiQuid IcE]

when i drive mine it feels like o/d is actually the first gear (before 1st) coz when i take it off, even at very low speeds, the revs go up like hippy said...

i always have mine on... feels like im saving petrol

[Scotty]

Hey, here's a question for you,

Traditionally I've left my OD on, I guess when rolling downhill at 60km/h, I feel like I saving a few cents on petrol, cos my car is revving lower,

But can I ask you, how about turning OD off to slow down. Like in a manual, quite often people gear up (or is that down?!?) into 3rd or 2nd gear to slow down, like when you approach a turn or something. Of, late I've been doing this like when turning, go down into 2, slightly braking then accelerating through the turn. Its great fun, but what part of my car am I phucking up???

Thanks