My clutch is completely shagged after 250K kms including 3 trips around Oz towing an 18' caravan.
My flywheel checks out ok. There is no noise upon stopping. A shagged DMF makes a clattering noise. The test for damper spring tension is ok. This is when you clamp the backplate then rotate the front plate with a breaker bar. The spring action should be smooth and no more than about 23mm of rotational movement with reasonable force on a 450mm bar. But the surface of the flywheel isn't perfect. You can't machine them because the front plate is designed to float so it can't be set up perfectly in a grinder. Also very few people have the machine that could rebalance the flywheels after any machining.
So maybe i'll replace the flywheel also or else i'll get judder and the driven plate will wear too fast.
On eBay there are Exedy conversion kits to single mass flywheel (SMF) with dampened driven plate for my Jackaroo 4JX1. The prices start at $1450.
I checked the price of genuine parts with Ramin Isuzu. Dual Mass Flywheel + clutch + thrust bearing + spigot bearing + a set of twist-to-torque flywheel bolts adds up to $1400 delivered.
So I have a choice.
I've been trying to find out if converting to a SMF flywheel effects the engine and gearbox. In theory it will be cheaper next time I need a clutch since I can machine the flywheel. But it's obvious that there will be a lot more strain on the gearteeth with the reduced dampening. However a feature of the 4JX1 is that it's gearbox is out of a truck so maybe it's tough enough. But a gearbox is a lot more expensive than a flywheel so it's worth thinking about.
My experience with this issue has been with a GQ Patrol diesel and a Commodore 5 speed. Both had DMF's so I converted them to SMF when their clutches went. It was a lot cheaper with those vehicles. The Commodore conversion was ok. The Patrol gave me problems. It had a weird feel to it, but the real problem was a vibration after fitting the conversion. At 1700rpm exactly there was a strong vibration. Above and below 1700 was ok.
It became so annoying I eventually I sold the vehicle for cheap. I figure the Patrol had problems because of the torque of the diesel engine.
Has anyone had experience with the Exedy SMF flywheel conversion? Does the 4JX1 get vibrations after the conversion?