Stupid question from a non motor head - Lock-up Torque Converter vs LSD

[2Muchmark]

So I'm considering buying another Camaro and was poking around on the GM order page when I noticed this. If I choose automatic transmission, I have to give up Limited Slip Differential. Is this item more or less replaced by the Lock-up Torque Converter? Or are these 2 completely different things and I now look like a total n00b?

[two_wheel_mayhem]

I think that's a weak move by Chevy.

And all modern automatics have a lock up convertor.

[Sir Nuke]

Originally Posted by 2Muchmark

So I'm considering buying another Camaro and was poking around on the GM order page when I noticed this. If I choose automatic transmission, I have to give up Limited Slip Differential. Is this item more or less replaced by the Lock-up Torque Converter? Or are these 2 completely different things and I now look like a total n00b?

i8ts just a goof up on the part of the Chevy website.....ALL V8's have a limited slip Diff. only the V6 Manuals have it.

[ihaveacamaro]

cool! I didn't know I had lim slip dif

[jd10013]

Originally Posted by ihaveacamaro

cool! I didn't know I had lim slip dif

neither did I. exactly what the hell is it
I'm familiar with the term, but not being a gear head I only have a rough idea of what it does and what the benefits of it are. anybody care to help?

[Bhobbs]

Basically what it does is when the drive wheel starts to slip on ice, water, dirt, etc, the differential locks and transfers power to the other wheel.

[el ess A]

This might help you understand a bit more about differentials and the different types:

http://www.howstuffworks.com/differential.htm

A bit of reading, but how else would a non-gear-head learn the basics?

[ChrisBlair]

Originally Posted by jd10013

neither did I. exactly what the hell is it
I'm familiar with the term, but not being a gear head I only have a rough idea of what it does and what the benefits of it are. anybody care to help?

GM used to call it 'positraction'. The simple definition back in the day was "transfer grip to the tire that slips". There's a clutch pack in there

Ever see the rubber marks put down by performance cars? The pair of tire marks is from a limited slip. The single mark is from an 'open' type. Used to be called a 'one legger' burnout.

One tangible effect is that the back end of your car can thrash around like a shark making a kill when you're really burning them up, with posi.

It's not a 'free pass' on loose dirt or ice, either, even though the description seems to indicate it makes that type of surface a snap

A limited-slip tries to drive both rear tires. It still has some slip by using clutches because when cornering the outside tires turn faster than the inside tires.

This is a nice description

[1BADLS3]

A torque converter lock-up I believe means the fins in the TC lock together and the trans becomes "like" a manual in a single gear where the engine is driving the gears directly through the input shaft versus when the TC is unlocked, it uses fluid pressure to drive the input shaft, which drives the gears.

Everyone already nailed the limited slip diff (LSD) definition.

It should be noted that LSD is different from a locking rear which can be electronic, mechanical/air, or inertia-lock (G80 rear end from GM) where the diff locks the rear wheels together when slippage is sensed. It unlocks at a predefined speed or when both wheels have traction. These are different from a "spool" --it was common in early racing to weld the rear spindles together inside an open differential so that both wheels were driving the car, which is important in hard cornering, especially if you've got one wheel off the ground.
So, there's OPEN, Limited Slip, Locking, and a Spool. You now have the fundamentals to imagine the different types of differentials and how they work

Oh, last thing...Chrysler also developed a neat feature for the open differentials on the base Wrangler. Whereas the high-rent models like the Rubicon come with manual locking front/rear diffs, the base wrangler has open differentials front and rear. It means the rig is effectively two-wheel drive (one front, one rear), making it almost useless in technical 4-wheeling.

So, because Wranglers already come with EBD (electronic brake force distribution), they made an additional feature called "Brake-lock differential". It's an open differential. When one wheel slips, as sensed by the traction control system, it can use the electronic braking module to apply the brake fully at the slipping wheel so that the open diff transfers power to the wheel that has traction. It's an ingenious idea, and basically added programming to equipment that's already on the rig since the module is used by the stability/traction programs. There's debate whether Limited Slip or Brake Lock is more useful in slick situations or technical 4-wheeling.

[shrinkdoc]

Originally Posted by Comrando

An open differential drives the easiest to spin rear tire.

A limited-slip tries to drive both rear tires. It still has some slip by using clutches because when cornering the outside tires turn faster than the inside tires.

The open rear-end is considered safer because driving both tires when they slip causes the rear of the car to move sideways. Driving only one tire allows the non-driven tire to retain traction and the rear won't have the same tendency to spin.

Its like a posi traction. I would be all over the place if I didnt have it because I spin my wheels pretty easily even with T/C on.

[squat]

This really old video gives the best explanation of a differential and what a limited slip would do for you. It's kind of annoying that the technology for this is 80 years old and it's still not standard on all cars...



http://youtu.be/yYAw79386WI

If anyone knows how to embed that into a post please do.

[two_wheel_mayhem]

[two_wheel_mayhem]

Originally Posted by squat

It's kind of annoying that the technology for this is 80 years old and it's still not standard on all cars.

Two reasons, cost and fuel mileage.

[squat]

How would limited slip effect fuel mileage?

Also, thank you for embedding the video, how did you manage to do it?