[cahme]

I've not found too much on the N55 clutch swap, so I'm starting this thread to get a list of parts needed & any special info needed. I'm planning to make this swap next weekend and am starting with the following:
HPF clutch swap diy
this diy post which includes the N54/N55 flywheel differences from 1addicts

Here are the parts I plan to use:
335is clutch kit: 21207603248 (clutch, power plate & bolts, throwout bearing)
Pilot Bearing: 21207536792
BellHousing bolts (x5): 11117587168
Rear Main Seal: 11117587168
Clutch Fork Pivot Pin: 21511223328
Clutch Alignment tool: 83300495449 (N54 version, will not work as-is)


Flywheel: 21207640733 (For Dual Mass, I could only find BMW @ $1k!!)
Flywheel bolts (x6): 11227520706

Trans Input Shaft Seal: 23127501712 (I did not change)
Trans Output Shaft Seal: 23118609228 (I did not change)

Downpipe to Exhaust gaskets: 18307553603 (I used Felpro 60308)

One thing I'm not sure about right now is the clutch alignment tool. I'm going to buy the N54 one and probably rig it to adapt for the pilot bearing being in the flywheel rather than the trans input shaft like the N54s.

For the flywheel, my plan is to re-use my existing one. I'm hoping I can find a shop in the DFW area that can check and/or resurface it, but I'm not buying a new one until I inspect mine first.

Currently, my clutch is slipping with JB4 in 3'rd under full boost at low-ish RPMs. It'll slip a few hundred RPMs then catch-up in this scenario. I've since gone to map 4 and there's no slip, so I'm putzing around there for the week.

If anyone has anything to add or correct if I may have it wrong, please reply and I'll try to keep this post edited with the correct/complete info.

[cahme]

I swapped out my clutch last weekend and here are my updates:

After reading this tool guide and various youtube videos, I decided my flywheel was okay. I ended up cleaning it with a scotch-brite on a drill and it cleaned up real nicely without any discoloring or hot-spots seen.

For the clutch alignment tool, I wrapped one end of a 10mm socket with paper and slid it in the n54 alignment tool. The paper created enough friction to hold the socket in the tool. I'm not certain it was needed as the flywheel has an indentation for the alignment tool to sit against, but I felt better knowing that I also had the tool (via the 10 mm socket) in the pilot bearing as well.

The pilot bearing swap was easy (with the flywheel removed) as it's pressed into the flywheel.

I was planning to do this with my car on jackstands in my garage, but I luckily found a co-worker who had a lift in his workshop and made it available to me. I would have done it on jackstands, but am real thankful I didn't have to

I can't really tell the difference in pedal feel, but for the 2 days when my car was down, I did all my driving on another manual tranny car with a significantly stiffer clutch, so my reference may have been distorted a bit.

Hopefully I'm good for another 118k miles now!

[Dhillon92]

Thanks for the review bud, glad everything went ad planned and better!

[Ozzie335i]

cahme, what kind of wheel power are you pushing?

[cahme]

I'm never dynoed. I'm pretty stock with just a chargepipe and JB4.

[AtlasM]

I'm looking at doing this 335is clutch swap on my '11 335xi N55.

I've been having an issue with my clutch pedal where it has kind of a hitch/pause in the travel when letting the clutch out. My mechanic believes it is a bad pressure plate.

I'm FBO with MHD Stage 2+ so figure it's worth upgrading the clutch to a 335is unit. Mechanic is fine with doing the swap as long as parts are confirmed correct.

Can you confirm that the parts list is exactly what is needed for doing the 335is clutch on an N55? Mechanic says he has the necessary clutch alignment tools already.

335is clutch kit: 21207603248 (clutch, pressure plate & bolts, throwout bearing)
Pilot Bearing: 21207536792
BellHousing bolts (x5): 11117587168
Rear Main Seal: 11117587168
Clutch Fork Pivot Pin: 21511223328
Flywheel bolts (x6): 11227520706
Downpipe to Exhaust gaskets: 18307553603 (or Felpro 60308)

Thanks!

[Ozzie335i]

Looks like a good list Atlas. You might consider changing the fluid, even if you recently had. Set it to zero. Also the bypass valve thing. Like 20 bucks. You know how to drive it now, do away with the clutch training wheels. As far as the rear main seal, people have commented not to change it if it isn't leaking. Supposedly the chances of changing it out and having the new one leak are higher than leaving a non leaking one alone. I bought it also, and it was not changed by my mechanic.

[AtlasM]

My CDV is deleted already and yes, I would plan on fresh trans fluid. I'll confirm with the mechanic on only replacing the rear main seal if needed.

I did some searching around RealOEM and it looks like other than the clutch kit itself, all the parts are the same for 335is N54T and 335xi N55. The flywheels are different part numbers but the pilot bearing is the same.

Clutch
E92 335xi N55 - http://www.realoem.com/bmw/enUS/show...27#21207567624

335is N54T - http://www.realoem.com/bmw/enUS/show...27#21207603248

Pilot bearing (on flywheel parts diagram)
E92 335xi N55 - http://www.realoem.com/bmw/enUS/show...87#21207536792

335is N54T - http://www.realoem.com/bmw/enUS/show...87#21207536792

According to RealOEM the 335is flywheel is 13.67 kg vs. 13.4 kg for the 335xi flywheel. If anything I'd want to get a 1M flywheel that lowers the weight to 11.4 kg. But it's also over $1000, and since this clutch job is a bit of a surprise to me, I'd rather not spend another $1000 on top of the surprise clutch job bill.

[cahme]

I can confirm those are the part numbers I used and have been fine on my car. I have about 27k miles since the swap (145k total) and everything is still fine. A couple of other comments now that I've re-read the thread:
- I forgot to put in the new fork pivot pin, so the original is still in there and holding up
- I did change out the rear main even though it wasn't leaking; it still isn't leaking
- I didn't change the rear tranny seal, but it started leaking about 2 weeks after the swap (I drove for over a week without the belly pan and was dry). I did change it afterwards and is still fine now .. I have no idea what happened for it to leak 2 weeks after the swap.

[AtlasM]

My mechanic did the job and included a new pivot pin. Basically all the parts are the same as for a regular clutch job, just substitute the 335is clutch kit (part # 21207603248).

Did not do a new rear main seal because actually I'm on a BMW remanufactured motor that was installed a year ago (long story) so no need to replace the seal.

Once I picked up the car, I realized how messed up my old clutch was. It's way easier to press the pedal, and on my old clutch, it was just...inconsistent. Lots of herky-jerky shifts and I was always doing a lot of clutch work to smooth it out. Even with the deleted CDV.

With the new clutch it's like a whole new car. I'm still re-learning how to shift smoothly, but I've found that I had developed a bunch of bad habits finessing the pedal with the old clutch that I don't need to do anymore. Shifts are instant and I totally get why people like the CDV delete, the 1-2 shift is great. This would probably be the case with a fresh 335xi clutch as well but it's nice to have the extra holding capacity of the 335is clutch.