My replacement DMF has gone bad after 45k kms. Anyone know if I can use the 5spd solid flywheel with the 6spd? The wrangler guys with the 4.0 seem to be able to retain their flywheels during a 5 to 6 speed swap - but it is a different tranny than the Libbys. This DMF appears at least an inch thicker than the pictures of the SMF I have seen. Anyone got a picture of a 5spd clutch/flywheel setup I can compare to my 6spd?

So I'm in the process of answering my own question. Picked up a junkyard flywheel from an '02 3.7. It is indeed a solid flywheel. It is identical in diameter to the DMF, the ring gear is in the same spot and the bolt pattern is the same. The fingers on the clutch cover appear to stick up more than the DMF one. I am having the flywheel machined and am going to try it with the SMF clutch disc and the DMF cover (it fits as well). Pics to come.

You might want to think twice about machining the flywheel. Apparently there is a slight curve to it and is only recommended to lightly scuff it if I remember correctly.

Found this someone quoted from the FSM:

"Flywheel machining is not recommended. The flywheel clutch surface is machined to a unique contour and machining will negate this feature. Minor flywheel scoring can be cleaned up by hand with 180 grit emery or with surface grinding equipment.
Remove only enough material to reduce scoring (approximately 0.001 -0.003 in.)

Heavy stock removal is not recommended Replace the flywheel if scoring is severe and deeper than 0.003 in.

Excessive stock removal can result in flywheel cracking or warpage after installation. it can also weaken the flywheel and interfere with proper clutch release."

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2003 Jeep Liberty Freedom Edition
3.7L 5 speed manual
OME 927/948 w/Bilsteins
245/75/16 Goodyear Duratracs

It's at a proper clutch/flywheel shop. I am assuming they know what they are doing when they said there wasn't a problem resurfacing it. They have proper flywheel grinders - not just a lathe like local parts stores.

I asked the flywheel shop guy about the convex surface and he said they just grind them flat. Doing some reading on the internet and it appears everyone quotes the FSM but no one can back up why not to machine them flat. It seems to have been done to try and smooth engagement, but has little effect. The flywheel I got had a surface on it that could not be cleaned up by a light scuffing - if it could have, I would have done that. I have no problem with having it ground - like every other clutch job I have done with zero problems afterwards.

Hopefully I will be able to get the SMF/clutch installed tomorrow and see how it works!

Interesting. Whenever I had a new clutch put it, I took a straight edge to my factory flywheel. It was perfectly straight with no curve at all. Either way, I did end up replacing it with a new one.

Curious to see how you make out after the machining.

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2003 Jeep Liberty Freedom Edition
3.7L 5 speed manual
OME 927/948 w/Bilsteins
245/75/16 Goodyear Duratracs

What motor is your 6 speed fitted to? I have been searching for a replacement solid flywheel for my CRD. Plenty of solid flywheel mods this side of the pond but have not found a replacement for the CRD.

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2005 KJ RENAGADE 2.8 CRD 6 SPEED NP242 FULLTIME 4X4

Mine is actually fitted to a 1.9L VW TDI motor with adapters to make the crank and block look like the 3.7.

Just discovered today I have 0.010" runout on my flywheel - probably due to the crank adapter. 0.003" is spec. This probably explains the early DMF failures (That and 300ft/lbs of torque and alot of towing). I am going to see if I can put some 0.010" shims in and compensate for that.

I also discovered that I could not use the DMF clutch cover - the fingers ended up too close to the clutch after tightning it down. But with a new clutch disc, the SMF clutch cover seems to work perfectly. One other thing I discovered is that the flywheel bolts for the DMF are too long and I needed to use SMF bolts.

Hopefully I will have it all back together tomorrow now.