Overdrive?

[Gs300Luver]

Hey.. My friend has an Ls400 (92 I think).. And we were debating about the overdrive button.. SO how exactly does that work.. When should you use it, and when shouldnt you use it.. Does it waste more gas or save?? Please help.. thanks.

[wwest]

Hey.. My friend has an Ls400 (92 I think).. And we were debating about the overdrive button.. SO how exactly does that work.. When should you use it, and when shouldnt you use it.. Does it waste more gas or save?? Please help.. thanks.

Basically, since the '92 has 2 engine knock sensors, you can ignore it. But my advice would be otherwise if you have an unusually heavy load or are towing one. In that case I would never leave it enabled except traveling on flat terrain or downhill.

But even with "standard" loading if you have a long climb ahead you can generally improve FE slightly by turning OD off. But then if you don't remember to turn it back on quickly you will can quickly lose anything you have gained. Which was likley not much anyway.

[Gs300Luver]

well.. What I heared was.. If you drive on the streets then turn it off.. But if your on the freeway and go mroe than 55mph, turn it on.. the RPM drops down.. which means saves more gas.. Right?

[wwest]

well.. What I heared was.. If you drive on the streets then turn it off.. But if your on the freeway and go mroe than 55mph, turn it on.. the RPM drops down.. which means saves more gas.. Right?

I would amend that to say leave it off when traveling, creeping, in relatively constant stop and go traffic. If you are moving along relative smoothly, even slowly, then OD can be of help for FE. Provided the engine ECU "thinks" so.

[aarman4]

Overdrive is a situation in which the cars wheels will be rotating at a higher rate than your cars engine crankshaft. It is meant to save fuel and reduce engine load, and if you are going very fast, it is an actual speed gear.

I turn my OD off when going down hills sometimes when I do not want to bother braking and just want a nice smooth slowdown.

Many people say not to use overdrive with trailers, and I agree with them. It may produce gear cycling in which the transmission jumps into overdrive and out of overdrive into the gear just below. However, if you are towing a trailer at highway speed (100km/h), then I do not imagine having using your Overdrive would be much of a problem unless you approached a hill.

[wwest]

Overdrive is a situation in which the cars wheels will be rotating at a higher rate than your cars engine crankshaft. It is meant to save fuel and reduce engine load, and

if you are going very fast, it is an actual speed gear.

Not many cars today can reach their highest speed in OD. OD is designed for low torque situations and at "high" speed there is typically so much friction and drag that the engine cannot deliver the required level of torque in OD.

I turn my OD off when going down hills sometimes when I do not want to bother braking and just want a nice smooth slowdown.

Many people say not to use overdrive with trailers, and I agree with them. It may produce gear cycling in which the transmission jumps into overdrive and out of overdrive into the gear just below. However, if you are towing a trailer at highway speed (100km/h),

then I do not imagine having using your Overdrive would be much of a problem

OD lockup clutches are typically not designed for continuous use in high torque conveyance conditions like towing a trailer or a car FULL of passengers and luggage.

unless you approached a hill.

Agreed, absolutely.

[eatingupblacktop]

Basically, in the city you want to minimize the tranny hunting which causes unnecessary wear and impinges on smooth operation. While cruising at highway speeds, O/D gives you better gas mileage, less noise and less wear. Also be carefull of overheating the tranny when engine braking in mountainous country down long grades. As far as towing goes, I've never seen an LS tow anything.

[aarman4]

lexls has a tutorial on installing a hitchkit. I plan on doing it this spring. I won;t use it much, but being far from civilization, it will be nice to have a trailer to grab the occasional load of home supplies and make up for not having a truck anymore.

[eatingupblacktop]

lexls has a tutorial on installing a hitchkit. I plan on doing it this spring. I won;t use it much, but being far from civilization, it will be nice to have a trailer to grab the occasional load of home supplies and make up for not having a truck anymore.

If you're in Brandon, sounds like you should have a truck. Winters must be killer. Just test drove an 03' 4runner with the 4.7L. Nice truck but the ride is truck. All of them come with the factory hitch. Tough and capable for sure, especially in the winter. Problem is, I'm used to the LS ride, so I'm going to check out the Highlander and compare. Would like to replace my winter Volvo with an AWD and start skiing again.

[aarman4]

Brandon is there just in case the occasional "really educated" Canadian recognizes it. I am in the sticks about 45 minute drive southwest of Brandon. In all honesty, I am unsure why ayone out here without a farm has a truck. They are very good at keeping the highways clear here, and with the rough condition the roads are in I never enjoyed any form of "truck ride" on them.

Also this is why I have no problem taking overdrive off for slowign down on hills ;) As anyone who has been here knows, a mountain in manitoba is similar to a fotthill in Vancouver, my previous city.

[wwest]

lexls has a tutorial on installing a hitchkit. I plan on doing it this spring. I won;t use it much, but being far from civilization, it will be nice to have a trailer to grab the occasional load of home supplies and make up for not having a truck anymore.

If you're in Brandon, sounds like you should have a truck. Winters must be killer. Just test drove an 03' 4runner with the 4.7L. Nice truck but the ride is truck. All of them come with the factory hitch. Tough and capable for sure, especially in the winter. Problem is, I'm used to the LS ride, so I'm going to check out the Highlander and compare. Would like to replace my winter Volvo with an AWD and start skiing again.

Watch out, lots of AWD's are NOT...!!

The HL, RX, and Sienna, for instance.