spwolf

because it is some kind of mechanical lsd, what else is it going to be if it is not electronical? lol.

MSMLexIS

I also read about the car having a semi limited slip in road and track. As for the audi with the limited slip that applies brake pressure to the wheel that slips the traction control in all lexus' does that.

05RollaXRS

That is kilowatt.

NotFatBoy

I think he is referring to ESP but whatever

4DOORFUN

Exactly. Limited slip is controlled by electronics. Wait, I mean "electronical".

The IS 350 DOES NOT have this: http://auto.howstuffworks.com/differential.htm

clubfoot

The Canadian IS350 with Sport Package has a mechanical LSD (Torsen) if I'm not mistaken.

spwolf

IS350 does not have differential? :-).

mkaresh

Lexus for the U.S. no doubt had to make some tough calls to keep the Sport Package's price down. Surely you know that power tilt/telescope and memory for the seats are more essential to a Sport Package than LSD?

Then again, in the U.S. neither the site nor the brochure list memory for the passenger seat, and it's definitely in the cars whenever memory for the driver seat is. So there is a chance that they just got sloppy and left LSD off the list as well.

Anyone have a Sport Package car yet? Maybe if you look underneath you'll see "torsen" cast into the differential housing

chuckb

01-05 GS have memory seat for driver only, and I believe ES and RX are same way.

XeroK00L

Good for you Canadia fellows. I wonder what stopped Lexus from making it available to its US customers. IMO that would've made the "Sport Package" actually worthy of its name.

4DOORFUN

Don't feel too bad, BMW 330 doesn't have a LSD either. You don't get one if you order their sport package either.

G35 is the only car in this class that offers a true LSD with their sport package. In fact, it comes standard on the 6 speed MT cars. It's an option on the auto transmission G35.

The Chad

http://www.lexus.ca/lexus/experience...r=2006#options

Looks like a true LSD is offered in the sport model of the Canadian version. If that's the case, then it should be adaptable to the US market car, or am I missing something?

BradmanOH

There are numerous types of LSDs out there and there are numerous opinions on which one is better. The most common type has clutch plates which limit the difference in the two half shaft speeds. These clutch plates can be adjusted (you have to take apart the differential) but it is all a compromise. If the plates are too tight then in every turn you will break free one of the wheels, which is what you are trying to avoid in the first place.

The easiest way to see if you have a LSD is to get on a slippery surface and give it some gas, if both wheels turn then you have some kind of LSD.

The next easiest way is to jack up the rear end of the car, and with the transmission in neutral, turn one of the rear wheels. If the other wheel follows the rotation of the one you turned, then you have some kind of LSD. On an open differential the opposite wheel will rotate in the opposite direction pretty easily.

To check the amount of slipping, do the same check with the other rear wheel on the ground. The amount of torque that it takes to rotate the driveshaft is how "tight" the LSD is.

When I looked at the underside of my IS350 the rear differential has a large finned back plate. This usually implies some sort of LSD function to cool the mechanism. I will bet that there is a LSD but it is set a bit loose, and the electronics keep things together. This is not a bad thing. If the LSD is too tight the car can be very hard to drive around a corner.

Bradman

4DOORFUN

Good points. However, you can have a LSD set pretty tight and still take corners. My Mustang GT has tight LSD and it's not controlled by electronics. When my car loses traction, BOTH tires simultaneously will spin on the pavement. It doesn't matter if I am turning a corner or going straight. That's how most sports cars are set up and the way I would prefer the IS to be. BTW - I'm not saying my Mustang GT is a sports car. It's far from it.