LSD - Ready to pull the trigger tell me what to get

[Matticus91]

I know I know.... I alone have started threads on this topic many times lol.

I'm ready to go for an LSD, tell me what to buy and why. Looking for people who have done this already and have experience with an LSD in their E82.

Car is a 2013 135i 6MT

I want to get a full pumpkin so I can bolt it right up

[jcrane82]

I went with the MFactory helical. Very happy so far, and I did the installation myself.

[desertman123]

How aggressive do you want it? Does popping while you turn in parking lots bother you?

Lotta guys run the MFactory, Quaife or Wavetrac LSDs.

[Matticus91]

Originally Posted by jcrane82

I went with the MFactory helical. Very happy so far, and I did the installation myself.

Can I ask which one specifically?

Originally Posted by desertman123

How aggressive do you want it? Does popping while you turn in parking lots bother you?

Lotta guys run the MFactory, Quaife or Wavetrac LSDs.

No popping, I want daily driveability maintained but I want it to hook if I hit it in the corners.

[desertman123]

Originally Posted by Matticus91

No popping, I want daily driveability maintained but I want it to hook if I hit it in the corners.

Probably get a helical then. Less maintenance too (over clutch-type)

[jcrane82]

I have a 128i, so I went this this one...

https://www.ecstuning.com/b-team-mfa...trs-05e46a~tm/

You need one made for the 135i case though.

[Matticus91]

Originally Posted by desertman123

Probably get a helical then. Less maintenance too (over clutch-type)

Originally Posted by jcrane82

I have a 128i, so I went this this one...

https://www.ecstuning.com/b-team-mfa...trs-05e46a~tm/

You need one made for the 135i case though.

Thanks for the info guys! Helical was what I was leaning towards after my many other discussions on this. Hoping someone with a 135i and swapped LSD will chime in. Also curious on if it's then worth coding out some of the stuff that controls the e-diff. I know there's a massive thread/discussion on that too I'll need to dive back into.

[jcrane82]

Originally Posted by Matticus91

Thanks for the info guys! Helical was what I was leaning towards after my many other discussions on this. Hoping someone with a 135i and swapped LSD will chime in. Also curious on if it's then worth coding out some of the stuff that controls the e-diff. I know there's a massive thread/discussion on that too I'll need to dive back into.

I coded out the e-LSD, as I could still feel the car intervening even with DTC/DSC turned off. I also coded off a lot of other electrical nannies and adjusted the understeer coefficients to allow the car more slip before intervening with DTC/DSC still on.

Also remember that you will need new bearings, seals, and more than likely shims.

[zx10guy]

Watching this thread.

I know I'll probably get smacked down for this as I know M Factory seems to be very popular here. But I do have reservations about going with M Factory because of an issue with some of their diffs some time ago. If I recall correctly, the bolts used on that production run failed causing some pretty catastrophic failures. While M Factory did replace affected units, I felt they should have gone a step further and at least covered some of the labor due to their mistake. If my accounting of the situation is incorrect, please provide any correction.

[chris_flies]

My advice:
1. Choose what type you want:
-Clutch type is generally more predictable and supposedly does much better when one wheel has no traction, but isn't as civilized and as "forgettable"
-Helical type is much more civilized, and is usually better (smoother) at putting power down, but can have issues with a zero traction situation (it then becomes an open diff)
-'Hybrid' type (Wavetrac, O.S. Giken) is the best of both. Wavetrac isn't nearly the diff that the 'Giken is, but it's far less expensive. Helical smoothness and civility with a smaller clutch pack (or 'Wave' lock) to lock the diff in zero traction situations

2. Choose which into you want.

3. Go out and enjoy it thoroughly.

I went with an MFactory 1.5-way Metal Plate LSD, and I fell in love with the car again. Rainy roads are a ton of fun, and the car is super predictable and stable. With the right fluid it's pretty civilized unless it's cold (it feels like it's welded pulling out of my neighborhood in the morning).

If you want to save some money, you can get an auto 135i diff case, and swap an LSD in yourself (auto's had bolted ring gears). I have all the tools, some shims if you break something, and a feeler guage to check backlash from me installing my diff myself.

[duder13]

I've started looking into this, too. I know it's not a great reason, but, among Quaife, Wavetrac and MFactory, I was thinking about MFactory just because it looks easiest to get installed, since they mail you the whole pumpkin assembled. lol

[ShocknAwe]

Got the 3.08 MFactory. Paired it with aluminium subframe bushings from Bimmerworld and stronger YCW axles. Turned out great. Stock like powerband, no hop or rear end wobble, predictable power oversteer, better traction, and I don't have to worry about breaking an axle, especially with the new MHD 2048 torque limiter shift bog fix for 6MT.

Any questions, let me know.

[Matticus91]

Originally Posted by ShocknAwe

Got the 3.08 MFactory. Paired it with aluminium subframe bushings from Bimmerworld and stronger YCW axles. Turned out great. Stock like powerband, no hop or rear end wobble, predictable power oversteer, better traction, and I don't have to worry about breaking an axle, especially with the new MHD 2048 torque limiter shift bog fix for 6MT.

Any questions, let me know.

Would you be comfortable doing a cost breakdown? Honestly this seems to be a pretty linear decision set as far as price vs value but it's good to hear opinions at each price point. If I could be at under 2k for just the Diff I'd be very happy.

Also did you do the full pumpkin or just diff?

[________]

I'm on the same boat OP.

Ready and willing.

I think I'm certain I want a Wavetrac Full pumpkin as well, and being that I'm in Canada there's less options that are cost-effective...

[Zombie_Head]

I am looking at the quaife LSD for my 125i, good reviews on them.

[chris_flies]

Originally Posted by Matticus91

Would you be comfortable doing a cost breakdown? Honestly this seems to be a pretty linear decision set as far as price vs value but it's good to hear opinions at each price point. If I could be at under 2k for just the Diff I'd be very happy.

Also did you do the full pumpkin or just diff?

I'll do one for my home-build diff:
MFactory Unit: $999.95
Donor 3.73 (328i Auto) Pumpkin: $150
MFactory Ring Gear Bolts: $30
*Australian Shim Kit: $200
*Snap Rings: $10

* = "Oops, that isn't supposed to come out that way!" costs

Very easy to get under $2k if you want to do it yourself (with an Auto donor diff because the manual diff has a welded ring gear).

MFactory also has complete units available; ECS has a shorter ratio 3.46 helical unit for $2149.95 or a standard ratio 3.08 helical unit (only ring and pinions + unit, no pumpkin) for $2599.96.

[Matticus91]

Originally Posted by chris_flies

I'll do one for my home-build diff:
MFactory Unit: $999.95
Donor 3.73 (328i Auto) Pumpkin: $150
MFactory Ring Gear Bolts: $30
*Australian Shim Kit: $200
*Snap Rings: $10

* = "Oops, that isn't supposed to come out that way!" costs

Very easy to get under $2k if you want to do it yourself (with an Auto donor diff because the manual diff has a welded ring gear).

MFactory also has complete units available; ECS has a shorter ratio 3.46 helical unit for $2149.95 or a standard ratio 3.08 helical unit (only ring and pinions + unit, no pumpkin) for $2599.96.

Tricky thing is my diff is welded so not sure I can do this the DIY way without the full pumpkin

[jcrane82]

You will want an auto differential to build up. The above cost breakdown by Chris is also missing new bearings. I know someone who was able to reuse his stock angular contact ball bearings (135is owner), but I would personally just get new bearings.

The nice thing about having to get an auto differential unit is that you can build up the differential yourself and then swap it in. When I installed the MFactory unit I didn't have a spare differential so the 128i out of commission until the installation was complete.

[chris_flies]

Originally Posted by Matticus91

Tricky thing is my diff is welded so not sure I can do this the DIY way without the full pumpkin

https://www.ecstuning.com/b-team-mfa...trs-05e9230kt/

This comes with the ring gear (and pinion to match) so all you have to do is pull the old open unit out, and swap with the locking unit: put the included ring gear on the locking unit, then swap pinion gears (I don't know if it's entirely necessary, or if the gears are simply made in pairs) and sail off into the sunset, sideways and smiling You keep your current casing, you're just swapping its guts.

Another option is to buy a used 135i Auto diff (which had a bolted ring gear), and swap the open diff with the locking one: pull the ring gear off the open unit, put it on the locking one, and voila! Sideways and smiling! With the auto diff, you also gain a shorter final drive ratio (3.46 versus the 6MT's 3.08). I went from a 3.23 to a 3.73, and it was an amazing improvement.

jcrane82 I didn't replace the bearings. The ones in my 90k-mile donor differential were flawless, and I really didn't want to have to reset backlash (shim kits are shockingly expensive). So far, so good...

[Dackelone]

Originally Posted by Matticus91

No popping, I want daily driveability maintained but I want it to hook if I hit it in the corners.

I think I would recommend a Quaife. It's quiet and it just works for street driving.

Since you want a complete pumpkin... Do you know about Birds in the UK ?

http://www.birdsauto.com/content/qua...w-and-mercedes


Dack

[jcrane82]

Originally Posted by chris_flies

jcrane82 I didn't replace the bearings. The ones in my 90k-mile donor differential were flawless, and I really didn't want to have to reset backlash (shim kits are shockingly expensive). So far, so good...

If you swap the open diff to a LSD you will need to set backlash. How did you install one, reuse OEM bearings, and not check/adjust backlash? Machining tolerances will be different from one unit to the next, and a couple thousandths of an inch matter.

[Matticus91]

Originally Posted by Dackelone

I think I would recommend a Quaife. It's quiet and it just works for street driving.

Since you want a complete pumpkin... Do you know about Birds in the UK ?

http://www.birdsauto.com/content/qua...w-and-mercedes


Dack

I haven't heard of them, and can't quite figure out what their deal is from the website lol. Do they sell diffs? I'm in the USA though and not sure it'd be financially reasonably to ship a diff over from the UK vs buying stateside