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Jay 535i
09-12-2005, 03:27 PM
Am I right in thinking that the point of an LSD is to quell wheelspin, and a car that never spins its wheels (like my auto 535) won't benefit from an LSD?

zygoteer
09-12-2005, 03:46 PM
Hmmm ... I can spin a wheel on dry tarmac when enthusiastically powering away from rest or accelerating fully out of some corners in my 535 auto, so I am keeping an eye out for a good used LSD going cheap.

The primary purpose of the LSD is to improve traction on difficult surfaces when laying the power down.
'Quelling wheelspin' is only an effect of this - but its easier/cheaper to simply lift off if thats what you want.

I suppose if you never get a loss of traction with your driving style, you would not notice the effects of an LSD, except maybe in the very slightly increased tyre wear.
However on wet/icy/snowy surfaces you would feel a difference.

Jeff N.
09-12-2005, 04:06 PM
Limited slip diffys help minimize wheel spin during low traction situations. If one wheel starts to spin (inner wheel in a corner, in the wet, etc) a clutching mechanism partially locks up the gears and transfers power to other axle.

For day to day driving, you won't notice an LS diffy much. For aggressive driving, it can help with power application in low traction situations.

It's not always your friend. For example, while an LSD can help you get started in the snow, it can also make a car more subseptible to swapping ends. An open diff will typically spin only one tire. The LSD will spin both causing a complete traction loss at the rear end of the car.

632 Regal
09-12-2005, 04:12 PM
Ill have to add that after popping in the LSD I got way worse traction in the snow, not sure why but I definetly lost some.


Limited slip diffys help minimize wheel spin during low traction situations. If one wheel starts to spin (inner wheel in a corner, in the wet, etc) a clutching mechanism partially locks up the gears and transfers power to other axle.

For day to day driving, you won't notice an LS diffy much. For aggressive driving, it can help with power application in low traction situations.

It's not always your friend. For example, while an LSD can help you get started in the snow, it can also make a car more subseptible to swapping ends. An open diff will typically spin only one tire. The LSD will spin both causing a complete traction loss at the rear end of the car.

Kalevera
09-12-2005, 04:27 PM
Yes, mine sucks in the snow as well...which is why I'm buying a winter beater.

best, whit

Jeff N.
09-12-2005, 04:47 PM
...dedicated snow tires make a huge difference. My 535 with some dedicated snow tires went just about everywhere with no problems. M+S tires were worthless.

632 Regal
09-12-2005, 04:51 PM
this was with snows, Im thinking that the spinning tire built more resistance traction by throwing the snow than 2 wheels spinning at half speed. It's a real chore to man that mountain of a driveway last year.

bjl4776
09-12-2005, 05:04 PM
It always made me laugh how the a LS was part of the cold weather package. The only time a LS is beneficial in the snow is from a standstill, but after that Id rather have an open ended

632 Regal
09-12-2005, 05:20 PM
unless you feel the need to do donuts on wet or snowey ground.

Alexlind123
09-12-2005, 05:40 PM
Yea, and lsd's are far better for drifting :)

Jay 535i
09-12-2005, 09:04 PM
How do I know if I have an LSD?

Kalevera
09-12-2005, 09:09 PM
Send me the last six digits of your VIN and I'll tell you.

Or look on the rear cover for a metal stamped tag. The prefix S indicates a limited slip. The car should have a S3.91 if it has one at all.

best, whit

Jay 535i
09-13-2005, 03:19 PM
Send me the last six digits of your VIN and I'll tell you.

Thanks, Whit. My VIN is WBAHD230XLBF63449.

motuman
09-13-2005, 04:22 PM
Yea, and lsd's are far better for drifting :)

Agreed.

After having driven the same 535 with and without LSD, I can confirm that it is much easier to induce power oversteer with the LSD.

JonE
09-13-2005, 08:08 PM
...dedicated snow tires make a huge difference. My 535 with some dedicated snow tires went just about everywhere with no problems. M+S tires were worthless.

100% agreement with this statement. Minnesota winters and e34=Blizzaks!