[FancyDan]

I'm strongly considering getting an LSD for my M240, as I believe it's the only thing holding it back from being the PERFECT car. I want to go with the M performance one for the warranty and to keep the car as OEM as possible.

What is a good price for the M performance LSD if purchased from a dealer? Does the part ever go on sale? I live in NY and will be getting the one with a 2.81 final drive if that makes a difference.

Just looking for a few data points to know what I should be aiming for. Really appreciate any insight.

[Sail Boat]

I would spend a couple hundred more and buy a wavetrac unit from Diffsonline. Drexler is great, but if you're going to spend $2,2-2,5 on a differential might as well go for more than 25-30% lock. I'd stay with the stock 3.08 ratio.

I've mentioned this a few times on this forum, perhaps too often, but a differential is of little use on the street and more performance can be had for less money. There's miles of improvement to be had with suspension, tires, and brakes. I'm not saying that a limited slip isn't a great upgrade; I've had multiple modern cars with them and they help on track, but I've found the street feel to be mostly cerebral.

[seansurfn2]

Originally Posted by Sail Boat

I would spend a couple hundred more and buy a wavetrac unit from Diffsonline. Drexler is great, but if you're going to spend $2,2-2,5 on a differential might as well go for more than 25-30% lock. I'd stay with the stock 3.08 ratio.

I've mentioned this a few times on this forum, perhaps too often, but a differential is of little use on the street and more performance can be had for less money. There's miles of improvement to be had with suspension, tires, and brakes. I'm not saying that a limited slip isn't a great upgrade; I've had multiple modern cars with them and they help on track, but I've found the street feel to be mostly cerebral.

x2 what he said

[SOLOMEK]

The upfront cost of the M-Diff will range from from (yikes!) used $850-ish to $2,300-$2,600 new.

Do not forget to research the install costs as well as these will vary wildly too. In most cases you will get what you pay for.

I know my path to the M-LSD would be bought new and dealer installed for full warranty on parts and labor. I like it that way.

[FancyDan]

Originally Posted by Sail Boat

I would spend a couple hundred more and buy a wavetrac unit from Diffsonline. Drexler is great, but if you're going to spend $2,2-2,5 on a differential might as well go for more than 25-30% lock. I'd stay with the stock 3.08 ratio.

I've mentioned this a few times on this forum, perhaps too often, but a differential is of little use on the street and more performance can be had for less money. There's miles of improvement to be had with suspension, tires, and brakes. I'm not saying that a limited slip isn't a great upgrade; I've had multiple modern cars with them and they help on track, but I've found the street feel to be mostly cerebral.

Appreciate the feedback, I'll definitely look through diffsonline. The stock ratio for the RWD auto is 2.81 btw. 3.08 is the stock ratio only for the RWD manual.

Totally valid points, but the reason why I am looking for an LSD is because I love going sideways in wide open areas. The eLSD in the car is adequate, but not really comparable to a mechanical LSD for this purpose.

My main reason for the M performance unit is that I'll get basically a 50k/ 4 year warranty on it, which I think is non-trivial for a unit that will see some moderate use.

[FancyDan]

Originally Posted by SOLOMEK

The upfront cost of the M-Diff will range from from (yikes!) used $850-ish to $2,300-$2,600 new.

Do not forget to research the install costs as well as these will vary wildly too. In most cases you will get what you pay for.

I know my path to the M-LSD would be bought new and dealer installed for full warranty on parts and labor. I like it that way.

Wow, where can you find used units for only $850? Not saying that's the direction I would go as I can only imagine what's been done to it, but I'm just curious.

Yeah, those are basically the prices I am seeing as well. $2600 is the sticker and the best price I can find third party is from ECStuning for $2300. I'm just curious if people have been able to negotiate better prices than that from dealers, or if they know when/if this part goes on sale.

[NISFAN]

Originally Posted by Sail Boat

I've mentioned this a few times on this forum, perhaps too often, but a differential is of little use on the street and more performance can be had for less money. There's miles of improvement to be had with suspension, tires, and brakes. I'm not saying that a limited slip isn't a great upgrade; I've had multiple modern cars with them and they help on track, but I've found the street feel to be mostly cerebral.

Couldn't disagree more.

I track my car but find the diff works more on the streets than at the track. Let's face it tracks are smooth surfaced with minimum speeds of 30mph and long radius corners that require smooth throttle inputs. The street is full of occasions where traction is compromised on an open diff, in fact there aren't many journeys I make where I don't feel the diff at work (Quaife).

[SOLOMEK]

Originally Posted by FancyDan

Wow, where can you find used units for only $850? Not saying that's the direction I would go as I can only imagine what's been done to it, but I'm just curious.

Yeah, those are basically the prices I am seeing as well. $2600 is the sticker and the best price I can find third party is from ECStuning for $2300. I'm just curious if people have been able to negotiate better prices than that from dealers, or if they know when/if this part goes on sale.

eBay. Once in a while you will see them pop up. My "yikes" comment was essentially what you said, "what the heck has this diff been through!!!"

[Phillymb75]

There is a discount code for buying accessories from the bmw website for 20% off, BMW20, it's good through the end of the year.

[gosi]

Originally Posted by NISFAN

Couldn't disagree more.

I track my car but find the diff works more on the streets than at the track. Let's face it tracks are smooth surfaced with minimum speeds of 30mph and long radius corners that require smooth throttle inputs. The street is full of occasions where traction is compromised on an open diff, in fact there aren't many journeys I make where I don't feel the diff at work (Quaife).

I agree with you disagreeing with him.

The diff makes the car hook up and makes it predictable and much more smooth vs the stock open one which frankly sucks. Better go with xdrive then.

[Pray for Mojo]

You can pick one up for about $2,200 sometimes a bit less. Lowest I've seen new was $1,800 on a black friday thing.

[rfranklin]

Originally Posted by FancyDan

Appreciate the feedback, I'll definitely look through diffsonline. The stock ratio for the RWD auto is 2.81 btw. 3.08 is the stock ratio only for the RWD manual.

Totally valid points, but the reason why I am looking for an LSD is because I love going sideways in wide open areas. The eLSD in the car is adequate, but not really comparable to a mechanical LSD for this purpose.

My main reason for the M performance unit is that I'll get basically a 50k/ 4 year warranty on it, which I think is non-trivial for a unit that will see some moderate use.

When Brian was still working at Sun Motorcars BMW, I picked up the M Performance LSD from him for $2060 shipped. I would call around to a few different dealers in your area to see what kinds of prices they can offer. Just speak to the parts manager directly and see if he/she can offer a better price. You might also have some luck looking up dealerships that sell parts on eBay and then contacting them directly for a quote. Dealerships that move higher volumes of parts will generally be able to offer better discounts. At the very least, if you are a BMW CCA member, you should be able to get a 10% discount off MSRP. I definitely think you'll be able to find someone who can beat that, though.

Regarding the warranty, the only way you will get it covered by the factory warranty is if you added it as an option at the sale. The M Performance LSD does come with a 2-year warranty, but the catch is that you will need to have it installed by a certified dealer. That's the way it was explained to me at least. When I had mine installed, it cost me around $1040.00 if I remember correctly. That included 6 hours of labor and 1L of differential fluid.

[msej449]

I don't track my car and can echo that the M Performance LSD makes an improvement on public roads. I paid the full price for a dealer retro-fit of the M Perf LSD in order to keep warranty, as I intend to keep my M235i indefinitely. Personally, I fell it's been worth it and that the M235i should have come with an LSD as standard - at least, if you use the car's performance, even within the limits of safety on a public road. Of course, this could just be buyer's confirmation bias, and if you just DD the car on an urban commute, you might not think it's worth the money (but then why have the performance version of the car anyway?).

[dradernh]

Originally Posted by FancyDan

Wow, where can you find used units for only $850?

~40% of retail for a used BMW performance part in good working order is a general rule-of-thumb; I'd be leery of buying any used clutch-pack diff, however

~60% of retail if it's new or if it can be shown it was only used lightly

While people sometimes choose to pay more, it's usually not necessary.

[XutvJet]

I paid $2,700 for the MP LSD, install labor at BMW, a bottle of LSD fluid, and tax. It was worth every penny. Like the others, the difference in traction and balance is astounding, even on the street. If you don't drive hard at all, then it's not for you. If you want the best driving version of the car you have, it's a must.

Here's my experience. https://www.2addicts.com/forums/show....php?t=1493261

[c-m]

Don’t you have to change the fluid after 2k miles of the initial install? Also, do you have to do some weird break in stuff?

I need to get one. Just curious about the process. Mine is mostly a track/weekend car.

[msej449]

@c-m There was no requirement to replace the fluid when I got my BMW M Performance LSD retrofitted by the dealer. The only other advice I got was to take it easy for the first few hundred miles.

You may find discussion on other threads about the efficacy of eventually replacing the Diff fluid, especially if you're tracking the car. But to my recollection this was in the longer-term.

Some posts elsewhere have recommended doing a load of figure-of-eights in an empty parking lot to 'exercise' the LSD. I asked about this on installation and the mechanics looked blank - they weren't aware of any internal service recommendations to this effect. However, given the forum comments, I used a freeway junction near me which has very-wide-radius 270° on/off ramps from a roundabout - I just took the car 'round these for half an hour every so often in case the 'exercise' / ''running-in' advice was valid.

[c-m]

Yeah. That’s what I heard as well. Good to know. Friend just installed his and was shocked by the figure eights and all that. LoL

[FancyDan]

Appreciate all the responses, guys.

Seems to me that $2000 is a good number to shoot for pre-labor and tax. Also good to know that the book time for labor is 3.5 hours.

I'll keep you guys posted if I decide to pull the trigger.

[XutvJet]

With respect to break-in, BMW's own literature states the following:

- 500 miles of sporty to moderate driving
- Constant acceleration in left and right hand turns to actuate the clutches (i.e. slow speed TIGHT figure 8s under load)
- Avoid launches

If you don't drive somewhat hard during break-in, you risk having an abrupt engaging LSD. The break-in seats the clutches and makes for a smoother operation.

https://f30.bimmerpost.com/forums/sh...d.php?t=982938

[msej449]

I saw the same documentation, but didn't interpret 'Constant acceleration in left and right hand turns' to mean doing close figure-of-eights. I read this to mean take the opportunity to stress the LSD on public roads where there were suitable progressive bends: something like a cloverleaf junction. Here's where I did this:


Although I appreciate that not everyone is fortunate enough to live close to a junction that's so useful (and such fun to drive and still remain inside road legal speeds). I can U-turn legally at a junction on the far right, or use a roundabout about a mile off-picture to the left. Nice thing about the whole setup is there is a roughly equal amount of left and right bends to take at around 60mph and still be legal.

[Edslittleworld]

Originally Posted by XutvJet

I paid $2,700 for the MP LSD, install labor at BMW, a bottle of LSD fluid, and tax. It was worth every penny. Like the others, the difference in traction and balance is astounding, even on the street. If you don't drive hard at all, then it's not for you. If you want the best driving version of the car you have, it's a must.

Here's my experience. https://www.2addicts.com/forums/show....php?t=1493261

Man...I'm quoted $2700 just for the parts at the dealership in Phoenix, AZ (Chandler BMW). They want another $1000+ for the install. What am I doing wrong?