Lsd On My Lexus

[Jonathan Roy]

I own a 1999 GS400, and I live in Canada.

I love driving my car all year round, but winter is a bit of a pain.

Rear wheel drive and 400 pounds of torque don't mix well.

I need to upgrade my differential to help out in slippery conditions.

What is best, Torsen diff or LSD?

Any recommendations on brand?

What is the right dimensions/model for my car?

Thank you for the help!

[1990LS400]

Was there some sort of special GS400 sold up there that had 400 ft-lb. of torque? The engines in the ones sold in the U.S. have a far lower torque rating. The engine in my 2000 LS400 is the same except with a bit more restrictive exhaust system that provides slightly less power and torque.

Have you had this car long? Are you using high quality and fairly new winter tires (with the mountain/snowflake logo) on your car in Winter? Do you have studs in your snow tires? -- Studs are allowed about half of the year in Quebec. Are you using the snow mode transmission setting and leaving the VSC on? Are you familiar with the drawbacks of limited slip differentials when driving on snow?

Here is a thread about LSD: http://en.wikipedia.org/wiki/Lysergic_acid_diethylamide

[Jonathan Roy]

Yes driving in winter while on LSD sounds verrry dangerous. You linked to LSD the drug.

Thanks for the quick reply.

About the torque I was wrong and I don't remember where I read that info.

I bought this car in June 2010 with 115,000 miles on the odometer.

Yes, I equipped my ride with decent ice/snow tires with no nails.

Yes, I do use the traction control on snow mode but it barely helps.

Yes, I am aware that limited slip differentials and torsen diffs can be dangerous while cornering under power on the slippery stuff.

Performance of the traction control is excellent in corners and braking. Even with traction off, the car handles the slippery stuff quite well.

The problem is getting out of my damned slippery driveway. (uphill)

Loading 40 pounds of sand bags in the back did help some, but that hurts front traction and gas mileage.

Questions:

- Does my GS400 have electronically controlled diff (where brakes are applied to the free spinning wheel to transfer power) ?

- Witch diff type will perform best with the included traction control ?

- What type/model/size do I need to remplace my current diff ?

[Jonathan Roy]

310 pound of torque = 420 newtons of force, I misunderstood the units on some European site.

[Jonathan Roy]

Ok then, no one here has advice on torsen diff versus limited slip / locking diffs ?

Then I want to know the size of the crown gear in my 1999 GS400 (4L V8)?

So I don't waste a week with my only car jacked up while I wait for parts to arrive.

[Jonathan Roy]

Ok I found the perfect page to explain the difference : http://www.houseofthud.com/differentials.html

So I'm going with a torsen or worm gear torque biasing differential.

But I still need to know the size/model needed.

[1990LS400]

Based on your question, I figured you hadn't had your car very long. Do you have/have had other vehicles that made it up your driveway? What were those? Are your winter tires in really good shape and have relatively few miles? It takes a lot of tread depth to cope with deep snow and even the best winter tires can fall below that tread depth by 12K to 15K miles. Maybe ask your Lexus dealer for advice. If your driveway is that steep, maybe you need a 4WD vehicle. I think you are going to find that you are wasting your money on LSD but ... well, everyone needs a hobby.

[Jonathan Roy]

Some front wheel drive cars have trouble when its all iced up.

My tires are bran new and came highly recommended by multiple sources.

You are still just trying to discourage me instead of helping me out with the info I seek.

This is frustrating, but I should not complain, this is free.