Overdrive

[vroom8]

Should I turn on my OD for the winter?

Is it better for slippery roads?

thanx!

[1990LS400]

Turn it on? Why would you turn it off? The "overdrive" on the gen 1 LS400 is not an overdrive at all in the traditional sense ... it's just a 4th transmission gear with a ratio of less than 1.00.

Leave overdrive on all the time unless you need to force a lower gear for some reason. On slippery roads, just use a light foot on the gas pedal.

What used to be considered an overdrive was a completely separate two speed transmission -- usually electrically controlled -- tacked on behind a usually manual three or four speed transmission. The last car I had with an electric switch controlled overdrive was a 1978 Volvo 242 with a Laycock de Normanville overdrive made in England. Here is an explanation of overdrives: http://en.wikipedia.org/wiki/Overdrive_(mechanics)

[vroom8]

Turn it on? Why would you turn it off? The "overdrive" on the gen 1 LS400 is not an overdrive at all in the traditional sense ... it's just a 4th transmission gear with a ratio of less than 1.00.

Leave overdrive on all the time unless you need to force a lower gear for some reason. On slippery roads, just use a light foot on the gas pedal.

What used to be considered an overdrive was a completely separate two speed transmission -- usually electrically controlled -- tacked on behind a usually manual three or four speed transmission. The last car I had with an electric switch controlled overdrive was a 1978 Volvo 242 with a Laycock de Normanville overdrive made in England. Here is an explanation of overdrives: http://en.wikipedia.org/wiki/Overdrive_(mechanics)

0, thank you....1990

I had turned it off thinking I could get better gas mileage...but after reading Wiki...I gues I will get better gas mileage with it on> thanks !

[killerFatty]

I like the hearts in the topic. Reminds me of Jcrome. BTW leave over-drive on all the time unless you are towing something up a hill. Especially on sllipy roads because you will have more torque going to the wheels without OD and there fore more chance of wheel spin.

[vroom8]

killer- yeah....I noticed that! my wheels spun on ice w/o it on.

thanks

wonder how jcrome is doing?

[VBdenny]

These LS400's have positraction which means both rear wheels spin equally. This is a big benefit on dry roads but on wet roads it can cause the car to get loose upon acceleration. Positraction requires special driving techniques so if you live in a snow climate, use snow tires.

[amcdonal86]

These LS400's have positraction which means both rear wheels spin equally.

The Lexus LS400s have open differentials with electronic traction control, not limited slip differentials. Both wheels do not necessarily spin equally.

[RDM]

And not all of them have the traction control either, it was an option, the majority of the 1st generation cars were sold without it. All it does is limit throttle application when wheelspin is detected, it's a very archaic design and does virtually nothing that a good driver couldn't do by just lifting off the throttle. Otherwise you're stuck with a typical open differential like most big cars are fitted with.

VB- clearly you don't know the difference here. Go watch "My Cousin Vinny" again then drive your car uphill in the rain.

[killerFatty]

limited slip or not, I expect snow tomorrow so I loaded four sand bags in the trunk today. Drive smart and the traction control which never works anyway, is pointless. I know, ironic coming from me right??

[amcdonal86]

And not all of them have the traction control either, it was an option, the majority of the 1st generation cars were sold without it. All it does is limit throttle application when wheelspin is detected, it's a very archaic design and does virtually nothing that a good driver couldn't do by just lifting off the throttle. Otherwise you're stuck with a typical open differential like most big cars are fitted with.

VB- clearly you don't know the difference here. Go watch "My Cousin Vinny" again then drive your car uphill in the rain.

Glad I wasn't the only one who was thinking of "My Cousin Vinny"!!!

Actually, the traction control in my '97 appears to also modulate the rear brakes individually. Then again, it appears that the second-gen LS had 4 channel ABS, and the first gen only had 3 channel, which probably prohibited using the brakes with the TCS.

[amcdonal86]

limited slip or not, I expect snow tomorrow so I loaded four sand bags in the trunk today. Drive smart and the traction control which never works anyway, is pointless. I know, ironic coming from me right??

I'm not sure if the TRAC system behaves really differently in your first-gen model than in my second-gen, but the TRAC system in my car is really useful. Testing it out in an empty parking lot, which TRAC on in the rain, it intervenes before the tail really starts to hang out (although it is still possible to spin out, but only if you do it intentionally). Without the TRAC, it's not that hard to spin out. My tests were all at around 20mph.

And yes, it is very ironic coming from you!

[vroom8]

I have been spinning all over the road! I don't have the traction option, but my tires are new, and don't seem to help. They are snow tires. I think I have forgotten how to drive on ice and snow!

I have loaded a couple sand bags in the trunk, too, but that doesn't even help.

[killerFatty]

We got some snow today. My trac does nothing but cut the throttle when it detects wheel spin, and that is only when it works. Which is almost never. Even with 4 sand bags in the trunk my wheels SPIN. On my way out of the parking lot tonight I couldn't give it any throttle. I had to Idle out onto the major roads. The only thing scarier than wheel spin on the snow is braking on the snow. That I think is much worse. When I went to hit my brakes I could barely rest my foot on the pedal before they lock up and the ABS kicks in. THAT IS SCARY. If you think about it, 4 sand bags only weighs 240LBS. (60lbs. each). This car wieghs close to 5000lbs fully fueled and passangered. 4900 and change on the door jam to be exact. Even if you put them right over the axle it still doesn't do much but hurt ride quality and make the LS look like a low rider. Throttle control is really all you can do besides dedicated snow tires like the firestone winterforce or bridgestone blizzaks. My current all season tires are only around 5/32 tread left and I can really tell it in the weather.

[amcdonal86]

We got some snow today. My trac does nothing but cut the throttle when it detects wheel spin, and that is only when it works. Which is almost never. Even with 4 sand bags in the trunk my wheels SPIN. On my way out of the parking lot tonight I couldn't give it any throttle. I had to Idle out onto the major roads. The only thing scarier than wheel spin on the snow is braking on the snow. That I think is much worse. When I went to hit my brakes I could barely rest my foot on the pedal before they lock up and the ABS kicks in. THAT IS SCARY. If you think about it, 4 sand bags only weighs 240LBS. (60lbs. each). This car wieghs close to 5000lbs fully fueled and passangered. 4900 and change on the door jam to be exact. Even if you put them right over the axle it still doesn't do much but hurt ride quality and make the LS look like a low rider. Throttle control is really all you can do besides dedicated snow tires like the firestone winterforce or bridgestone blizzaks. My current all season tires are only around 5/32 tread left and I can really tell it in the weather.

Hahaha, why are you still driving in the snow? Haven't you learned your lesson? :P

Also, from what you said, the first-gen TRAC system works very differently from the second-gen one. That, or yours is busted.

[eatingupblacktop]

I have been spinning all over the road! I don't have the traction option, but my tires are new, and don't seem to help. They are snow tires. I think I have forgotten how to drive on ice and snow!

I have loaded a couple sand bags in the trunk, too, but that doesn't even help.

Even without Trac Control, if you're riding snow tires, you should be able to feather the throttle enough to prevent spinning and sliding. I would make sure your front brakes aren't dragging. It doesn't take much to affect your traction in the snow.

[amcdonal86]

I have been spinning all over the road! I don't have the traction option, but my tires are new, and don't seem to help. They are snow tires. I think I have forgotten how to drive on ice and snow!

I have loaded a couple sand bags in the trunk, too, but that doesn't even help.

Even without Trac Control, if you're riding snow tires, you should be able to feather the throttle enough to prevent spinning and sliding. I would make sure your front brakes aren't dragging. It doesn't take much to affect your traction in the snow.

I think he implied that he does not have snow tires.

[eatingupblacktop]

I have been spinning all over the road! I don't have the traction option, but my tires are new, and don't seem to help. They are snow tires. I think I have forgotten how to drive on ice and snow!

I have loaded a couple sand bags in the trunk, too, but that doesn't even help.

Even without Trac Control, if you're riding snow tires, you should be able to feather the throttle enough to prevent spinning and sliding. I would make sure your front brakes aren't dragging. It doesn't take much to affect your traction in the snow.

I think he implied that he does not have snow tires.

I don't know, she did say "They are snow tires." So maybe I'm just not understanding her correctly.

[amcdonal86]

Bah, I thought you were talking about killerfatty. My bad!

[vroom8]

I have been spinning all over the road! I don't have the traction option, but my tires are new, and don't seem to help. They are snow tires. I think I have forgotten how to drive on ice and snow!

I have loaded a couple sand bags in the trunk, too, but that doesn't even help.

Even without Trac Control, if you're riding snow tires, you should be able to feather the throttle enough to prevent spinning and sliding. I would make sure your front brakes aren't dragging. It doesn't take much to affect your traction in the snow.

You know, I don't remember spinning around this much last year, with the sand bags in the trunk, and I drove all winter...I will check out my brakes, blacktop...thanks.

[vroom8]

I have been spinning all over the road! I don't have the traction option, but my tires are new, and don't seem to help. They are snow tires. I think I have forgotten how to drive on ice and snow!

I have loaded a couple sand bags in the trunk, too, but that doesn't even help.

Even without Trac Control, if you're riding snow tires, you should be able to feather the throttle enough to prevent spinning and sliding. I would make sure your front brakes aren't dragging. It doesn't take much to affect your traction in the snow.

I think he implied that he does not have snow tires.

I don't know, she did say "They are snow tires." So maybe I'm just not understanding her correctly.

Yes, they are snow tires...brand new ones. Not seeming to help.

[vyhanh]

For all you guys explaining this, if ya'll look like Marisa Tomei, then I will believe you !!!