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**sapote** · 04-03-2022, 10:48 PM

If the clutch stack is soo thick that the bolted down cap has a gap then they are not within tolerance. This has nothing to do with the shims to reduce the spiders/side-gear plays.

**TwoD** · 04-05-2022, 07:10 AM

Seems to me maybe you got the wrong clutch pack/disks. I would try to get ahold of diffsonline, in my experience they are not the best with answering the phone but respond quickly via email. good luck!

**Epoustouflant** · 04-05-2022, 07:13 AM

I have seen many issues with these. Hit up @bavariandiffs on IG or DM me there @m3_epoustouflant. I will connect you.

He has done testing with these and gathered feedback from other diff guys. It’s not good.

**stash1** · 04-05-2022, 08:29 AM

Originally posted by Epoustouflant View Post

I have seen many issues with these. Hit up @bavariandiffs on IG or DM me there @m3_epoustouflant. I will connect you.

He has done testing with these and gathered feedback from other diff guys. It’s not good.

Interesting, haven't really heard too much negative stuff regarding Racingdiffs (specific to our platform) until now. Hmmm...can you say more?

**Epoustouflant** · 04-05-2022, 09:03 AM

Originally posted by stash1 View Post

Interesting, haven't really heard too much negative stuff regarding Racingdiffs (specific to our platform) until now. Hmmm...can you say more?

The shims are not manufactured to proper tolerances and the coating is subpar. They supposedly last less than a few thousand miles, less if you track. Not an isolated case - just seems like a poor product from the pros I chatted with.

You can also talk with Florian @ Limited-Slip.de - he's very knowledgable as well. I know Jonathan @ BavarianDiffs better as we chat often.

**Arith2** · 04-06-2022, 05:19 PM

They're a Serbian company that sells cheap parts. Not much more to say. I wouldn't really call them experts on the E46 M3. They're quite impact happy in their "How to" video as well. There are no specs posted and they seem to sell products without proper testing. They probably mean well but good intentions don't fix your diff. I would find a proper clutch kit and buy that. There have been few instances of these clutches failing rather quickly.

**bigjae46** · 04-06-2022, 07:03 PM

You have to remove the OE shims. Ask the builder if he has any parts left over. If he says no then he did not rebuild it properly.

I've rebuilt 6 of these with the Racingdiffs clutches...have not had an issue. Check my build thread. I have the 4 clutch conversion. I've put about a 20 days of track time on the clutches, pulled them apart and the clutches and steels look great.

**fattycharged** · 04-06-2022, 08:10 PM

Originally posted by bigjae46 View Post

You have to remove the OE shims. Ask the builder if he has any parts left over. If he says no then he did not rebuild it properly.

I've rebuilt 6 of these with the Racingdiffs clutches...have not had an issue. Check my build thread. I have the 4 clutch conversion. I've put about a 20 days of track time on the clutches, pulled them apart and the clutches and steels look great.

soon to be 7

**mrgizmo04** · 04-06-2022, 10:21 PM

All right guys, appreciate all the comments.

Sapote, there is a large bevel washer that goes on top of the clutches at the very end before closing the lid. The first one you are thinking about is the smaller one that goes on the opposite side under the first side gear, so there are 2 washers sandwiching everything together.

So...I just spent about 2 hours in my garage rebuilding the spare spare v1 lsd unit (yes, I ordered several kits from racingdiffs, and needed to try myself before going nuclear to blast them on all social media and start a refund for parts that didn't work)...I needed to go through the motions of what the diff builder is experiencing, he is not a BMW diff guy, he usually puts in pre-assembled lsd units...

The only spare part to Jae's point, that I had left over, is the first small flat washer under the first side gear. My diff did not have those thin clutch looking spacers/washers (not sure which ones do, but I know some do).

Diff builder's experience with the clutches where the teeth needed to be ground down... Yes mine were tight and would not go on freely, a little tapping with the hammer got them on. I think it was just some overspray friction material on the teeth, so no biggie there.

The gap that my builder has at the end...I had a gap almost 1/4 inch wide between the end cap and the lsd unit, after stacking everything together and putting the cap on, but before tightening the final 4x 4mm allens. I tried pushing the cap with my weight and felt the preload shim acting like a spring, which is what it's supposed to do. I then put my foot down on the middle of the lsd unit to push the cap on (essentially sitting on the lsd unit) and tightened the 4x 4mm allens. Gap closed.

Moral of the story, everything is doable, I think my diff builder not being familiar with this lsd unit and racingdiffs kit is being a bit conservative, he did call me saying he didn't want to crack the clutch discs by hammering them and didn't want to strip the 4x 4mm allens. I'll call him tomorrow and double check that he has the original flat washer from under bottom spider gear out (some of those are hard to separate due to oil tension), and if he does, to put the f-ing thing in a vice and tighten the 4x 4mm allens.

Kinda false alarm, but maybe good info for others trying to do this.

I didn't take a picture of mine, but from racingdiffs video screenshot below - you can also see about 1/4 inch gap once everything is stacked but the cap is not yet tightened.

Jae - that step of me sitting on the cap to help close the gap while tightening the 4x allens (or if I had a vice I'd use it), is that relatively inline with what is supposed to happen? To be honest I think the 4x allens would have pulled the gap closed on their own, unassisted, but they are small and I guess in interest of not stripping the small 4mm head assistance was precautionary.

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**mrgizmo04** · 04-06-2022, 10:54 PM

Overall guys, to add some more info about my experience with racingdiffs...

When I was ordering parts, (and those who know me, I dive super deep into details to get everything squared away before I do the job, to eliminate unknowns), Luka and his team responded to all my questions via emails. I noted a few things that didn't make sense to me that I would change on the site (I discussed in another thread) how the advanced vs basic kit descriptions and bundling do not address e46 m3 specifically, due to the change in v1 vs v2 lsd units mid production and what bearings/preload shims are included for v2 in e46 vs e92/etc. They made sure I got all the right parts with an extra large shim for a v2 kit (since everything is the same for e46 between v1 and v2 kits except for the thicker large shim), in case I wanted to use one of the rebuild kits for a v2 unit.

I also asked him to make a few extra explanatory/clarifying videos on how to shim the lsd unit for backlash adjustment, which he did.

His team did provide me with specs that I asked for, like pinion torque resistance, etc, when I was planning to do the whole thing myself.

I don't know what happened in the last month or so with silence, but given proximity to what is going on in Ukraine, things could be tough with family situations.

In terms of how long the clutches will last, I know they will not last long...that was the point of me getting several v1 rebuild kits and converting my diff with v2 unit in it to a v1. Quick swap out of the clutches and off you go, without having to adjust backlash/etc. I was avoiding making a final decision and the $ to go wavetrac vs giken vs drexler.

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**bigjae46** · 04-07-2022, 05:07 AM

I don’t reinstall those 4 small bolts. They don’t do anything. I just bolt the ring gear on. Those bolts are seized half the times.

It is harder to get the cap on because the shim increases preload. You should measure breakaway torque as a double check.

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**mrgizmo04** · 04-07-2022, 08:19 AM

Originally posted by bigjae46 View Post

I don’t reinstall those 4 small bolts. They don’t do anything. I just bolt the ring gear on. Those bolts are seized half the times.

It is harder to get the cap on because the shim increases preload. You should measure breakaway torque as a double check.

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Yep, similar to the set screws on the rotors, just a pain and at the end of the day lug nuts hold everything together anyway.

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**sapote** · 04-07-2022, 02:26 PM

Originally posted by mrgizmo04 View Post

Sapote, there is a large bevel washer that goes on top of the clutches at the very end before closing the lid. The first one you are thinking about is the smaller one that goes on the opposite side under the first side gear, so there are 2 washers sandwiching everything together.

So...I just spent about 2 hours in my garage rebuilding the spare spare v1 lsd unit (yes, I ordered several kits from racingdiffs, and needed to try myself before going nuclear to blast them on all social media and start a refund for parts that didn't work)...I needed to go through the motions of what the diff builder is experiencing, he is not a BMW diff guy, he usually puts in pre-assembled lsd units...

The only spare part to Jae's point, that I had left over, is the first small flat washer under the first side gear. My diff did not have those thin clutch looking spacers/washers (not sure which ones do, but I know some do).

Be careful or you might end up with a constant locking LSD, or the clutch stack pushing on the left side-gear which is wrong.

“Sapote, there is a large bevel washer that goes on top of the clutches at the very end before closing the lid”
My understanding is there is no washer/shim between the cover (hydraulic pump) and the clutch stack. If the lid is at the top, then I would say this washer is at the bottom of the clutch stack, not the top.

“The first one you are thinking about is the smaller one that goes on the opposite side under the first side gear”
First side gear or 2^nd side gear, depending during removing or installing, and it’s ambiguity. I suggest to use left or right side-gear.
The right side gear has the bevel shim (new part), and the left side gear has none as it is thrusted by the splined clutch core and the pump shaft.
The large thick washer should be between the left side gear and the clutch stack. Its function is to prevent the clutch stack from pushing on the left side gear (this washer rests against the carrier body).

“My diff did not have those thin clutch looking spacers/washers (not sure which ones do, but I know some do).”
Not sure what you’re refereeing to, but there should be a washer between the clutch stack and the left side-gear.

**eacmen** · 04-07-2022, 04:56 PM

Originally posted by bigjae46 View Post

I don’t reinstall those 4 small bolts. They don’t do anything. I just bolt the ring gear on. Those bolts are seized half the times.

It is harder to get the cap on because the shim increases preload. You should measure breakaway torque as a double check.

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Whats the breakaway torque range for a healthy OEM LSD?

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Racingdiffs tolerance issue and contact

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