[STR8-6IX]

if you are not at the limit of adhesion around corners I dont imagine it will do much, but any sort of sliding/oversteer will be alot better. you will also have better traction off the line.

[jpnh]

Originally Posted by 6IX-F10-N52

if you are not at the limit of adhesion around corners I dont imagine it will do much, but any sort of sliding/oversteer will be alot better. you will also have better traction off the line.

Its also a bonus for folks with a RWD F22 that drive in the snow.......

[STR8-6IX]

Originally Posted by jpnh

Its also a bonus for folks with a RWD F22 that drive in the snow.......

certainly. My car was RWD only for this model year and i wish i had an LSD..

how are they in the snow compared to open diff?

[jpnh]

Originally Posted by 6IX-F10-N52

certainly. My car was RWD only for this model year and i wish i had an LSD..

how are they in the snow compared to open diff?

The difference is profound.

100#'s in the trunk helps too

[BEM-S4]

Originally Posted by jpnh

The difference is profound.

100#'s in the trunk helps too

If you mount studless ice and snow tires and put 100lbs sand in the trunk you will be total fine no LSD. Just be a bit careful cornering at speed the back end will be a tiny bit more ready to step out on you.

[jpnh]

Originally Posted by BEM-S4

If you mount studless ice and snow tires and put 100lbs sand in the trunk you will be total fine no LSD. Just be a bit careful cornering at speed the back end will be a tiny bit more ready to step out on you.

So, my car came with open diff and I added it after the fact

Was/Am using Hakka R2's and had same weight in the trunk

The difference after the addition of LSD is profound.....when I say this, I'm reflecting on how much better it performs on going UP the "Cliff" of a hill I live on in snow.

[BEM-S4]

Originally Posted by jpnh

So, my car came with open diff and I added it after the fact

Was/Am using Hakka R2's and had same weight in the trunk

The difference after the addition of LSD is profound.....when I say this, I'm reflecting on how much better it performs on going UP the "Cliff" of a hill I live on in snow.

Oh it's better no doubt - although the car is more than fine in the snow without as long as it's also equipped with a driver with some common sense.

[jpnh]

Originally Posted by BEM-S4

Oh it's better no doubt - although the car is more than fine in the snow without as long as it's also equipped with a driver with some common sense.

So, the "cliff" i live on is steep enough and long enough that the right tools dictate whether the car stays at the bottom of the hill and I walk 1/2 a mile OR whether I have a nice warm ride UP the hill.

Most of my neighbors run studded snows to add perspective.

[BEM-S4]

Originally Posted by jpnh

So, the "cliff" i live on is steep enough and long enough that the right tools dictate whether the car stays at the bottom of the hill and I walk 1/2 a mile OR whether I have a nice warm ride UP the hill.

Most of my neighbors run studded snows to add perspective.

Yikes that sounds bad. That hill aside though you were probably fine otherwise before you went LSD right?

This shit is the worst in the northeast with the hills. Midwest soooo much easier.

[mdputnam]

These LSD threads usually fall into a fairly predictable pattern. Those that say you don’t need it for driving around town and others that say you do citing all sorts of performance benefits. So, to the question that continually pops up here; Do I need a limited slip differential? The short answer is no, you don’t need a limited slip differential. But then, if you look into your soul of souls and really think about it, you don’t need 13.4 inch four piston disc brakes, or a 320 horsepower direct injection 3.0 liter engine, or Adaptive M suspension with variable damper control. In fact you don’t need a BMW! I suspect though that you wanted a BMW, most likely because it is a fun car to drive, looks cool, and has a reputation for being, for want of a better moniker, "the ultimate driving machine". These are all very good reasons that entered in to your illogical decision to spend $50,000.00 on a sports coupe that is smaller and less practical than a $15,000.00 Toyota Corolla.

But, what makes it the ultimate driving machine? Is it the laser focused design of the car to maximize performance and handling above all else? Or is it a cleverly effective marketing plan designed to make you feel good on the road as you crush your enemies, see them driven before you, and hear the lamentations of their women? Where you fall on that spectrum, marketing versus performance, determines to some degree whether you purchase a limited slip differential. Let’s face it, BMW put in an open differential as standard equipment for one reason and one reason only, to lower the cost of the car by 5%. This is a logical move from a profit standpoint as it widens the appeal to a broader audience, most of whom wouldn’t even be able to tell you where the differential is let alone describe the difference between an electronically assisted open differential and a limited slip differential.

So, dear reader you don’t need one, but if you’re in the small minority that believes an overly expensive high performance sedan should have a performance differential, get one whether you need it or not. The rest can be content knowing they are driving one of the coolest best handling cars on the market.

[jpnh]

Originally Posted by BEM-S4

Yikes that sounds bad. That hill aside though you were probably fine otherwise before you went LSD right?

This shit is the worst in the northeast with the hills. Midwest soooo much easier.

The first and last 1/2 mile of my ride is the most "Interesting"

Heading out if you blow the 45 degree down hill left hand turn onto the 1 lane bridge at the BOTTOM of the hill you go off a 20' embankment into a river.

This same geography makes it challenging to get much of a running start up the multi pitch climb....where the steepest section is the last......

Its so bad my oil guy told me I better plan ahead because he wont go up my hill for a couple days after a snow storm.........

Cant tell you how many times I've had to "Plow" a set of tracks up the hill and back down to take 2-5 additional "Plow" runs before I could make it UP the whole hill........this hill is a natural barrier to neighbors who are not particularly hearty

[jpnh]

Originally Posted by mdputnam

So, dear reader you don’t need one, but if you’re in the small minority that believes an overly expensive high performance sedan should have a performance differential, get one.

not to be picky but its a Coupe not a Sedan

[overcoil]

Don't limited slip differentials lose their efficiency over time?

I had read years ago that rear differentials with clutch packs lose efficiency rather quickly.

But how about other types of limited slips?

[Beartato]

Originally Posted by ScottSinger

Don't limited slip differentials lose their efficiency over time?

I had read years ago that rear differentials with clutch packs lose efficiency rather quickly.

But how about other types of limited slips?

Torque biasing types (Quaife, Wavetrac) don't wear like a clutch type due to using helical gears instead of clutch mechanisms for its operation.

[Poochie]

Originally Posted by mdputnam

These LSD threads usually fall into a fairly predictable pattern. Those that say you don’t need it for driving around town and others that say you do citing all sorts of performance benefits. So, to the question that continually pops up here; Do I need a limited slip differential? The short answer is no, you don’t need a limited slip differential. But then, if you look into your soul of souls and really think about it, you don’t need 13.4 inch four piston disc brakes, or a 320 horsepower direct injection 3.0 liter engine, or Adaptive M suspension with variable damper control. In fact you don’t need a BMW! I suspect though that you wanted a BMW, most likely because it is a fun car to drive, looks cool, and has a reputation for being, for want of a better moniker, "the ultimate driving machine". These are all very good reasons that entered in to your illogical decision to spend $50,000.00 on a sports coupe that is smaller and less practical than a $15,000.00 Toyota Corolla.

But, what makes it the ultimate driving machine? Is it the laser focused design of the car to maximize performance and handling above all else? Or is it a cleverly effective marketing plan designed to make you feel good on the road as you crush your enemies, see them driven before you, and hear the lamentations of their women? Where you fall on that spectrum, marketing versus performance, determines to some degree whether you purchase a limited slip differential. Let’s face it, BMW put in an open differential as standard equipment for one reason and one reason only, to lower the cost of the car by 5%. This is a logical move from a profit standpoint as it widens the appeal to a broader audience, most of whom wouldn’t even be able to tell you where the differential is let alone describe the difference between an electronically assisted open differential and a limited slip differential.

So, dear reader you don’t need one, but if you’re in the small minority that believes an overly expensive high performance sedan should have a performance differential, get one whether you need it or not. The rest can be content knowing they are driving one of the coolest best handling cars on the market.

You did an excellent job summarizing the never ending debate of LSD or Not to LSD and the simple fact is that BMW chose omit an LSD from their mainline vehicles because years of research has indicated that a majority of (?US?) customers are more concern with M badges, M wheels, M umbrellas, ect, than a mechanical part they can't brag to their friends about. I can't count how many times I get into conversations with M4 owners and ask about their electronically controlled torque-vectoring LSD benefits and they look at me like I have a third ass cheek or something, followed by comments like; "Yea and my wheels are soo big and purrrty"
Point being is that you can't blame BMW for the smart strategy of not including an LSD stock, even though the brake-based fake ELSD KILLS the power around spirited corners. It saves them money and in turn, they pass alone the savings to us in the form of a lower sticker price (imagine how many M badges we can buy now..) I am just grateful that BMW listened to us minority drivers, all the way from the E90 days and at lease offered the MP LSD as an option, regardless of the cost.. I have one and I don't regret the money spent at all (No more DSC flashing) If you have to ask about an LSD, you probably need one..

[evilalien]

TL;DR: No. It isn't.

I suspect that driving it all the time in ways that an LSD is important for would get you frequent tickets and/or arrests

You can always add one later if you find RWD with an open diff and DSC insufficient.

[HeyMoe53]

I have another solution. I could just revert back to driving my boring but serviceable Ford Focus all the time, and put on the snow tires every winter.

And, I could use the savings to spend most of the winter somewhere warm, every year.

If I was worried about badges and such, I would have put all sorts of crap on my 1-series.

And, thanks for calling me "dear reader." I'll remember that when I go to the gym tomorrow. Think I'll throw an extra plate on every bar--I always work out better if I am a bit irritated ; )

[Kolyan2k]

Originally Posted by mdputnam

These LSD threads usually fall into a fairly predictable pattern. Those that say you don’t need it for driving around town and others that say you do citing all sorts of performance benefits. So, to the question that continually pops up here; Do I need a limited slip differential? The short answer is no, you don’t need a limited slip differential. But then, if you look into your soul of souls and really think about it, you don’t need 13.4 inch four piston disc brakes, or a 320 horsepower direct injection 3.0 liter engine, or Adaptive M suspension with variable damper control. In fact you don’t need a BMW! I suspect though that you wanted a BMW, most likely because it is a fun car to drive, looks cool, and has a reputation for being, for want of a better moniker, "the ultimate driving machine". These are all very good reasons that entered in to your illogical decision to spend $50,000.00 on a sports coupe that is smaller and less practical than a $15,000.00 Toyota Corolla.

And since we all pick that 13.4 inch four piston brakes, the 320hp 3.0 inline 6, and the M adaptive suspension, the short answer is YES we do need that M-PERFORMANCE LSD as well

[jpnh]

Originally Posted by Kolyan2k

And since we all pick that 13.4 inch four piston brakes, the 320hp 3.0 inline 6, and the M adaptive suspension, the short answer is YES we do need that M-PERFORMANCE LSD as well

This is really it......

[kdog26372]

I added an LSD on my tuned 135i and never tracked that car. You won't notice much if anything from a straight-line acceleration standpoint, at least I didn't. I noticed it most when making sharper turns. Without the LSD the car's traction control and other nannies would kick in and you simply wouldn't accelerate, but rather pause and accelerate not so fast until the car was pointed straight again. With the LSD you could aggressively make turns without the interference. Now this was the 135i and I know of an m235 with xdrive and I find if I put it in sport plus mode it rarely if ever has the same issues as the 135i did without LSD so maybe the 235i is a little less intrusive, but it may just be xdrive vs RWD.

It's a nice to have, not a got to have as you can turn off most of the interfering stuff and most will find this sufficiently sporty.

[XutvJet]

I'm telling you, drive around in DSC OFF and take note of just how easy it is to get the rear wheels to spin in a drift, lay equal tracks of rubber, etc. I NEVER see any DSC lights flashing because all the nannies are off. The eLSD is pretty dang good in most all situations. Add really sticky rubber and you may be hard pressed to find a measurable difference in lap times on most tracks.

[HeyMoe53]

Again, thanks for the replies. Still thinking about it. Not that it is about the money, but minus metallic paint, and heated seats, that's half of the cost of an LSD. Something to think about, because I am a bit on the thrifty side (thanks, Dad). I've never slid my 128. But, that is 100 HP less.