Flywheel replacement

[Kdubski]

What's the consensus on replacing flywheels? Word on the street is that LUK recommends replacing it every other clutch. I am replacing the clutch as a preventative measure as I have the engine out. With LUK's recommendation, is it OK to install an un-resurfaced flywheel with a new clutch?

[heinzboehmer]

You can get away with reusing the flywheel if the surface is undamaged. However, a new LUK one is about ~$400 on FCP (which means you never have to pay for it again). I changed mine when I swapped my clutch because of this.

https://www.fcpeuro.com/products/bmw-clutch-flywheel-z4-m3-dmf050

[bigjae46]

Street driven, you can probably get 2 clutches out of a flywheel. If I were paying someone to do the work then I would replace it. If I were DIY'ing it and wanted to take a chance...I would reuse it.

For a track car, I'd look at the JB Racing Flywheel KNOWING it will be noisy but it has a replaceable friction surface.

[Radekxpl]

Easy way to tell weather flywheel needs replacing or not is by amount of movement between the 2 masses. You can do that by counting the teeth on the first mass while rotating second mass per LUk product catalogue max allowable range is 4 theeth or 13 degrees ( each tooth equals 3.25 Degree) of movement anything over flywheel needs replacing. Brand NEW OE LUK flywheel has 2 tooth movement. Just did my clutch at 151k and my flywheel had 4 tooth movement so I replaced it, my clutch was original as well. Look in attached pdf for part # 415 0175 10 on the list

[Arith2]

Street driven, you can probably get 2 clutches out of a flywheel. If I were paying someone to do the work then I would replace it. If I were DIY'ing it and wanted to take a chance...I would reuse it.

For a track car, I'd look at the JB Racing Flywheel KNOWING it will be noisy but it has a replaceable friction surface.

My JB Flywheel is not loud at all. It really only makes noise when I decelerate. Idle is pretty much quiet. Harmonics have changed slightly from 1000-2500rpm but it's like it really isn't there. My SMG works with it. I've put 1500 miles on it. The reason I bring this up is because I used the LUK clutch kit with it. SMG driving has to be adjusted and it was like learning to drive one all over again with the slight throttle lifting on shifts.

As for OP the biggest concern would be evidence of any hot spots. That would be bluing of the metal and discoloration. Looks like you can choose to replace it or keep it.

[Altaran]

Single mass flywheel always causes some sort of gear chatter. Though I do not find it very noisy and it is only at idle and below 2,5k rpm. If you run solid tranny mounts it does get more noisy 😉