Need quick advice re: South Bend clutch vibration

First, thanks in advance for any advice you can provide!

I am a longtime member, but first-time poster in this forum (previously a Mk3 owner, many moons ago). I am in the process of buying a very nice, well-maintained 2011 Sportwagen, and the previous owner had the clutch replaced with a South Bend kit. It drives GREAT, but there is a slight vibration when accelerating through the gears at around 2000rpm. It last for maybe a couple of hundred rpm, and I assume that it's part of the clutch/flywheel characteristics of the SB kit.

In reading about these clutches, I see that some folks have experienced synchro failure after installation, and I am wondering whether this should be a concern for me on an otherwise-stock vehicle. Are those who are experiencing synchro failures more heavily tuned? Should I consider a damper? Will a mild tune (the most I'd ever do, as I plan to daily drive this car -- I'd be after mpg increases and maybe a little power, if anything) help with the vibration, possibly?


For reference, car is a 2011 with 118k on the odometer. Clutch was replaced after previous owner experienced a "pedal to the floor" failure -- DMF failure maybe? Timing belt service was completed at 100k and car is very clean... I'm excited to have found it! Again, thank you in advance!

Sounds like a great find.

My Southbend clutch is very smooth once engaged. I find that the roughest part is the engagement. Mine is a Stage 2 Endurance kit. I had it replaced after the first kit had a clutch disc failure. Even the first kit was smooth when engaged.

Does your kit have a DMF or SMF? Most of the SB kits that I have seen for MK4 and MK5 models come with a matching SMF.

I would think that if there is a DMF as part of your kit, it would be less prone to vibrate as it has built in dampening. Was the clutch recently replaced when the timing belt was done?

Does your car have a 6 speed manual trans? If this is the case, the slave cylinder is located inside the bell housing so if the seals go, you get brake fluid all over the clutch resulting in the need to drop the trans to sort it out.

I wonder if the vibration is engine related or engine mount related.

If your SBC is the single mass kit and the car's stock you might want to change it out with a new clutch with a DMF. The SBC kit does vibrate a fair amount and can damage synchros. A fluiddpr can help. SBC saw this was enough of an issue with the 02Q transmission that they no longer sell that kit.

Thanks, folks. Yes, it's a manual transmission and I gather that the kit was indeed the one with the single mass from what the seller stated. The vibration is pretty subtle, but it's there; I wondered whether it was enough to be concerned about synchro wear. The rest of the car is indeed stock, but a tune is not out of the question if it might help smooth things out. Would that or a fluid damper be a better investment early on?

To answer the other questions, the timing belt and clutch were done separately, but both within the last year and a half or so. I think the clutch was within the last year.

Thank you both again!

Tune won't help the vibration. I was wondering why the PO used a SMF kit if the car is stock: Most people use them in modified cars. If it were my car I'd swap the clutch sooner rather than later: cheaper than rebuilding the transmission.

IndigoBlueWagon said:

Tune won't help the vibration. I was wondering why the PO used a SMF kit if the car is stock: Most people use them in modified cars. If it were my car I'd swap the clutch sooner rather than later: cheaper than rebuilding the transmission.

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X's 2!, what indigo said^ . Altho this is the smoothest diesel Ive ever owned Id never trust a SMF from all the failures repoorted here. Since the P.O. modified to a SMF is it possible he used some sort of poly mounts? (vibration). I would like to know more about the dampner upgrade myself, certainly couldnt hurt.

Thank you all again -- your input is very much appreciated. I'll weigh my options... p.o. used the SBC kit on a recommendation, as he intended to keep the car long-term and tune it. (Wound up getting a work vehicle for his commute, so the TDI was offered for sale) He was very upfront about the vibration and increased clutch noise at idle, and said that his shop said that was normal for the single mass clutch, but something to be aware of. I may install a Fluidampr and see whether that helps; it looks super easy.

That leads me to my next question: is grinding of the timing cover required for the Fluidampr installation? I have seen someone mention that it is, and others indicate that it's not. In any case, for under $400 I can give it a try and then decide whether to go full clutch swap.

Again, your advice is very much appreciated!

Grinding the timing cover sounds familiar. I don't think Fluidampr really makes a product specifically for TDIs. Keep in mind that they also only last a year or so.

IndigoBlueWagon said:

Grinding the timing cover sounds familiar. I don't think Fluidampr really makes a product specifically for TDIs. Keep in mind that they also only last a year or so.

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Thank you again... this is all helpful!

IndigoBlueWagon said:

Tune won't help the vibration. I was wondering why the PO used a SMF kit if the car is stock: Most people use them in modified cars. If it were my car I'd swap the clutch sooner rather than later: cheaper than rebuilding the transmission.

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On this subject... I'm guessing that I'd need to swap back to dual mass flywheel AND change the South Bend clutch itself too, correct? There's probably not a DMF that will work with the SB clutch, is there? Just looking at parts cost to do this swap. Thanks!

No, you'd have to change both flywheel and clutch kit. Something like this: https://www.idparts.com/luk-dmf-clutch-flywheel-kit-20l-tdi-speed-p-5577.html

IndigoBlueWagon said:

No, you'd have to change both flywheel and clutch kit. Something like this: https://www.idparts.com/luk-dmf-clutch-flywheel-kit-20l-tdi-speed-p-5577.html

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That's what I figured. Looks like if I can't find the time (and a lift!) to do it myself, I'm looking at ~$500-600 for labor on a clutch, no?

Thank you!

More like $900-1000 in labor for a clutch job typically. I'd pass on that car. Even if you can negotiate a couple grand lower on price due to the problematic mods, there may be significant damage done to the gearbox already.

Damn... thanks folks. This is a tough one. Car is very nice, 118K on the odometer and receipts (from dealership) for full timing belt service and oil changes, and it's $6800. You can see why I'm so tempted. Damn...

PO made a $2,000 mistake. If he's willing to drop the price then it could still be a good deal.

IndigoBlueWagon said:

PO made a $2,000 mistake. If he's willing to drop the price then it could still be a good deal.

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That's what I'm wrestling with; couldn't agree more, and truly do appreciate your opinion(s). He's already come down a bit on price, but I don't want to beat him up too badly. I'll have to mull it over a bit. I, too, fear that the synchros may already be compromised.

Thank you all again.