LSD Diff clutch pack second source?

[sapote]

The single source that people bought the clutch set, is currently listed at $440 and I think it is too much for what it is. I don't even like their spring shims to have zero backlash on the spider gears, and will not use these shims.
Looking at this clutch supplier https://www.raybestospowertrain.com/
Their clutch catalog lists the datasheet with ID, OD, number of teeth, thickness. Maybe we can find an alternative clutch set for our M3 - just the driven friction discs and reuse the driving steel discs if they are in good condition. If not in the catalog, maybe ask the supplier to make a production run for us, doing a group-buy?

https://global-uploads.webflow.com/5c5b471f76e86765efb73e1b/5d67c32d46f65dec08f3b5d7_RaybestosPowertrain_Friction_Specifications.pdf

[nahvkolaj]

This is probably not what you’re looking for, but what I have on my radar:

https://racingdiffs.com/products/bmw-m3-m5-m6-z4m-lsd-differential-rebuild-kit?variant=42497704788204

[sapote]

This is probably not what you’re looking for, but what I have on my radar:

https://racingdiffs.com/products/bmw...42497704788204

$440 is too much for what they are.

[Tones]

Than make it your self?

Sent from my Pixel 6 using Tapatalk

[sapote]

Than make it your self?

Sent from my Pixel 6 using Tapatalk

No, but we can find the clutch plates by checking the industry catalogs. $200 or less is a fair price, but $440 is too much for the parts, and we don't need to replace the steel plates.

[Cubieman]

Interested in alternatives as well, just bought a diff. that I plan fully to re-build as well as fix the free play issue.

Should be interesting, hope I don't mess it up as it wasn't that cheap.

[bigjae46]

You can try and get them through the OEM. I don't see what the issue is with the belleville springs? You can just not install the small spring for the spider gears.

Their ZF 4 clutch conversion kit is working well. Haven't had an issue or complaint with the V1 LSD. The V2 LSD kit has been a different story. Likely installer related. The V2 unit is far more complex.

I can sort of agree on the V2 unit that the free play shim (small one) is less necessary since the small spider gears are pinned to the case. I haven't heard of the M-clunk being a problem on the E9X M3s which use the same diff carrier

[sapote]

You can try and get them through the OEM. I don't see what the issue is with the belleville springs? You can just not install the small spring for the spider gears.

Not very sure, but I'm thinking why the factory didn't just use the Belleville spring spacer -- one size fits all instead of the more laborious of measuring the clutch thickness and adding the proper shim as needed. With the Belleville instead of solid shim, the LSD lock up action is less effective due to the compliant of the spring which prevents the locking piston to press with full power on the clutch stack (when one wheel spinning faster than the other). So instead of 60% lock it might only has 40% lock.
If I do the work, I would measure the clutch stack total thickness, the space in the carrier from the piston to the bottom plate, then add the shim as needed for the suggested 100Nm preload. At first, it will be a trial error process of finding the relationship of (clutch stack + shim) thickness T vs. preload .

[sapote]

Interested in alternatives as well, just bought a diff. that I plan fully to re-build as well as fix the free play issue.

Should be interesting, hope I don't mess it up as it wasn't that cheap.

V1 or V2?
As long as you don't mix up the output flange bearing shims, and not removing the pinion shaft, then the ring/pinion mesh is not changed then you will not be close to messing anything. The LSD is fairly simple work and you will not be able mess up anything. My advice is don't use the Bellville shim for the side gear and the clutch stack, but select the flat shims for the proper adjustment.
V1: For the side gear and spiders gear backlash, add shims under the RH side side gear to reduce the total backlash to about 2mm rotational arc on the side gear, and don't try to get to zero backlash as this will cause more wear on the spider rods.
V2: the shims have to be added under both side-gears, as the spider rods are not floating as on V1.
Just post questions as needed and we will help to answer them.
If you have V1 spare, then disassemble the LSD and measure the number of teeth, ID and OD on the clutch plate, then we can work on finding the second source for these clutch plates.

[Cubieman]

V1 or V2?
As long as you don't mix up the output flange bearing shims, and not removing the pinion shaft, then the ring/pinion mesh is not changed then you will not be close to messing anything. The LSD is fairly simple work and you will not be able mess up anything. My advice is don't use the Bellville shim for the side gear and the clutch stack, but select the flat shims for the proper adjustment.
V1: For the side gear and spiders gear backlash, add shims under the RH side side gear to reduce the total backlash to about 2mm rotational arc on the side gear, and don't try to get to zero backlash as this will cause more wear on the spider rods.
V2: the shims have to be added under both side-gears, as the spider rods are not floating as on V1.
Just post questions as needed and we will help to answer them.
If you have V1 spare, then disassemble the LSD and measure the number of teeth, ID and OD on the clutch plate, then we can work on finding the second source for these clutch plates.

I'll find out which version it is on Wednesday when I get it, I'll need to come up with a jig or something to work on it, uncharted territory for me.

Thanks for the info, Im quite sure I will be in need of some help when I get into this project!

[bigjae46]

I'll find out which version it is on Wednesday when I get it, I'll need to come up with a jig or something to work on it, uncharted territory for me.

Thanks for the info, Im quite sure I will be in need of some help when I get into this project!

If you decide against DIYing it, I have a jig to do a V2 LSD. $150 to rebuild the LSD pumpkin.

If its a V1, I use a c-clamp to keep the end cap on while you remove those stupid 4mm hex bolts. Hit it with some heat and be careful. Otherwise the end cap is going to start to lift and strip the screws.

[Cubieman]

If you decide against DIYing it, I have a jig to do a V2 LSD. $150 to rebuild the LSD pumpkin.

If its a V1, I use a c-clamp to keep the end cap on while you remove those stupid 4mm hex bolts. Hit it with some heat and be careful. Otherwise the end cap is going to start to lift and strip the screws.

I don't have a press or even a solidly mounted workbench at this point, figured this is my excuse for those things. I'll need to start seeing what tools I need for this.

I want to attempt it and I also want to give stock gearing a try as well but if it's simply too much you'll most definitely be hearing from me.

[bigjae46]

I don't have a press or even a solidly mounted workbench at this point, figured this is my excuse for those things. I'll need to start seeing what tools I need for this.

I want to attempt it and I also want to give stock gearing a try as well but if it's simply too much you'll most definitely be hearing from me.

You need:

1. A really good and big bench vise.
2. circlip pliers
3. extra axle bolts (V2 only)
4. make a tool to turn the output flange on the bench - square steel tube with 3 bolts in it (V2 only)
5. torque wrench to measure breakaway torque (V2 only)
6. 2 or 3 jaw puller or you can dremel the carrier bearings off
7. mandrel for carrier openings (to press on)
8. press for carrier bearings (could use bench vise, wouldn't recommend)
9. mandrel to press on inner race on carrier bearings
10. chisel
11. BFH
12. IIRC - 19mm socket for the ring gear bolts
13. Opening tool (V2 only)

That's all I can think of.

Let me know if you need any help.

[sapote]

If its a V1, I use a c-clamp to keep the end cap on while you remove those stupid 4mm hex bolts. Hit it with some heat and be careful. Otherwise the end cap is going to start to lift and strip the screws.

Is this only true for LSD that has the Belleville shim on the clutch stack? The stock LSD without the spring shim should not push on the end cap the whole way, especially with worn down clutches.

[sapote]

I don't have a press or even a solidly mounted workbench at this point, figured this is my excuse for those things. I'll need to start seeing what tools I need for this.

Assuming you will get the V1, and if the output flange bearings are smooth then no need to replace them, then no need for the press, but you need a big bend mounted vise to hold the carrier with a pipe inserted in the carrier round hole to lock it from spin around the vise. I think in most case with a Diff from a junk yard, only the clutch need to be replaced or shimmed up, and reduce backlash on the side-gear.