BMW 135i – 335is/550i Clutch Upgrade

2017 Update: This 335is/550i clutch setup held up great for 22k hard miles! I have absolutely no complaints. In June I decided to upgrade to MMP Stage 3 turbos and chase 700whp. I knew this clutch setup wouldn’t hold, so I removed it and replaced it with a SPEC Stage 3+ unit.

After adding my aggressive E85 flash last summer, the factory clutch started to slip. I decided it was time to upgrade so I could enjoy the car to it’s full potential this summer. From Spec to ACT, there are plenty of aftermarket options available. Then I found the 335is/550i clutch upgrade on ECSTuning, so I started to do some research.

This clutch comes factory in the F10 550i, which puts down 443 tq and weighs a whopping 4552 lbs. DINAN doesn’t offer a clutch upgrade for their different stages of 550i’s, so apparently they feel that it is adequate. Their Stage 3 550i puts down 580 tq and they kept the factory clutch. Also, someone on the forums is using this clutch and claims that it is holding at over 620wtq on aftermarket turbos. To me, it sounds like the clutch is severely underrated.

My 135i won’t see more than 500 tq anytime soon. I’d guess that it is currently around 420whp/465wtq, but only weighs 3300 lbs!

I decided to give it a try. Here is my parts list from ECSTuning:

When replacing your clutch, I highly advise that you also replace the factory dual-mass flywheel (DMFW). The springs wear over time and will eventually let go. I chose to go with a lighter, single-mass flywheel (SMFW) from MFactory for $499.95 shipped. This brought my total parts cost to $1044.12, not bad.

DMFW vs. SMFW could be debated for hours, but it all comes down to what you want out of the car. If you care about noise, go with a DMFW. The SMFW chatters a little bit, especially with the A/C on. However, the DMFW is known for having issues at high horsepower levels. If you plan on upgrading to aftermarket turbos, you will want a SMFW. SMFW also rev faster because there is less rotating mass. OEM and aftermarket DMFWs are available on ECSTuning. I chose the SMFW because this is now a performance car. It is no longer stock and will never return to the car it once was from the factory.

Here is a video I recorded after install with the SMFW chatter:

Let’s get down to the dirty stuff… old clutch:
Old 135i clutch Old clutch and flywheelStill some life left on the friction disc, but some slipping spots with heat damage on the pressure plate. Everything else was ‘okay’. The new rear main seal was installed and the transmission was removed.
New rear main seal 6MT out of the car 6MT out of the carSee those two bottles of Redline D4 ATF on the table? We drained the old fluid out and added about 1.5 quarts until it started overflowing. After that, the new clutch and flywheel were bolted on.
MFactory SMFW 335is/550i clutchLastly, everything goes back together in reverse order. Obviously I didn’t get pictures of everything during the install, but it all went together flawlessly. Big thanks to my buddy Kevin, who did an awesome job with the install. He took great care of the car!

Once the car was finished, I took it out for a test drive and it feels fantastic. The clutch pedal is slightly stiffer, but retains an OEM feel. The gear changes are nice and smooth with the new Redline fluid. Everything grabs like it should and I’m very satisfied with the new setup! It will be put to the test this summer…

44 thoughts on “BMW 135i – 335is/550i Clutch Upgrade”

    1. I can’t remember. My buddy Kevin did the clutch job while I worked on some other stuff. He had his own alignment tool from previous N54 cars.

    1. Clutch has been holding up great! It’s definitely being put to the test. Almost Over 8,000 hard miles on it. Took the car to the drags a few times and have done many pulls. No slipping.

      1. That is great to know, I have a 07 335i e92 FBO with meth and clutch is going out, was on the fence between the spec 2+ and the 335is clutch. I want to take the car to the track and the drag strip. Was afraid of having to do the clutch job twice if I went with the 335is clutch, but I guess ill give it a try!

  1. How are you liking the M Factory flywheel? In previous cars I have experienced a lot of noise when swapping flywheels, how are the noise levels with this one?

  2. Hey! I came across your blog through one of the forums, and while scrolling through, I found that we have the exact same clutch and flywheel setup! Mine’s currently got about 3k miles on it and feels super good.

  3. Obviously the clutch itself is from the 550i and the flywheel is aftermarket, but regarding all the bolts and bearings were they for the 135i? Or is everything you bought in the clutch kit 550i specific?

  4. Did you only use 1 set of the Aluminum Bolts (5)? I thought there were more than just 5 bolts holding the transmission to the engine. Asking because I’m using this list to buy all the supplies for my clutch job. Thanks!

    1. Yes, only 1 set of 5 is required. There are more bolts, but they are not alu and can be reused.

  5. Did you have to remove the air intake that is on the back of the head to get access to the upper starter bolt and bell housing bolt?

    1. I’ve been running it at an estimated 425whp/465wtq without an issue. I’ve read of people going over 500whp without a problem, but no facts to back it up. I should be pushing close to that now that I’m FBO E85 with inlets. We will see!

  6. Funny, couldn’t you have eliminated more chatter using a smfw clutch disk instead of the solid 335is clutch disk without springs?
    I know it’s a high performance car and all, but I’m just saying so maybe some of the rest of us can gauge what route to take should we take on a smfw

  7. Can you advise me on what spark plugs to use pal? So many people using different types now. Many thanks. How s the car going? Still good I hope

  8. Thank you thank you thank you! Your website is such a great resource. Thanks for taking the time to write and post pics of what’s doin’. Much appreciated.

    1. Everything has been holding up just fine. I’ve been VERY hard on the car for about 18k miles now with the upgraded clutch. Tons of launches and roll races. No slipping.

  9. How is your engagement? I just had this exact setup installed. The chatter at idle has been remedied by raising the idle to 900rpm, but in-gear chatter at low rpm and load >2300rpm is really terrible.
    The clutch grabs extremely high and the pedal feels like it has a bit of a hiccup / stick in the first 1/2″ of travel.
    Thanks for posting this up.

    1. Alex,

      The engagement for me is completely normal. I don’t feel any hiccups or sticking – no complaints. I also raised my idle to accommodate for the chatter.

    1. Interesting take on SMFW vs. DMFW. I’ve had absolutely no issues with my SMFW. It’s been thousands of miles and it’s been ABUSED. Still holding up strong, no slipping or odd noises – I’m happy with my decision. It looks like that video has more “thumbs down” than “thumbs up”, and the comments are disabled. In my opinion, that shows they’re worried others will prove their theory wrong.

  10. Hey i planing on doing this on my fbo 335i but with the DMFW insted… Will IT hold the same power as with the SMFW? I have no E85 yet.

  11. Do you remember if the new clutch disc was sprung or unsprung?
    im trying to do some part number research and I’ve come up with 2 separate clutches for the 550i
    21207573789 and 21207603248 (the one listed on ECS)
    Im looking at the LUK kits as i see in your pics and ECS, that its a LUK clutch not BMW OEM. i come up with 2 numbers 03-079 and 03-081, matching the above numbers respectively. I’ve gotta upgrade the clutch on my 135i, its not even close to FBO, just 95k miles and started to let go first time I took it to the track. Good write up and thanks!

    1. Hey Mike, I’m glad you like the write-up! The clutch disc was unsprung. However, I’ve since replaced the clutch with a Spec Stage 3+ because I upgraded turbos and am chasing more power. The 335is/550i clutch was great to me, never slipped!

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