LUCKY_LARUE60
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Changing a DMF to a SMF (The Lucky Mod)
The "Lucky Mod"
Changing a Dual-Mass to a Single-Mass Flywheel
By Jim Williams (Lucky Larue)
When taking out the flywheel be careful as this thing is heavy, and it weighs around 65lbs.
One thing if for any reason you have any concerns don't try this . This is at your own risk, Mel Agne has done this conversion and so far it has worked out great, I have not put this in my truck as of yet but have it ready as my flywheel is making noise and I have this ready when I do change the clutch out I will change this out also. I am not afraid of using this fix, I feel really safe doing this to my truck.
I strongly suggest you drill out the bolt holes on a GOOD drill press to make sure the holes are straight. It would not be a bad idea to check the balance after putting it back together before installing it.
There is a guy on E-Bay that has made a DMF hub that dose the very same thing I have done and he wants $200 plus shipping for the hub, that is where I got my idea and tore a flywheel apart and discovered this trick This fix will cost you whatever the price of the 6 grade 8, 3/8 X 2" fine threaded bolts & lock nuts and about an hour of your time drilling out the holes and bolting it all back together once you have the flywheel out.
After removing the flywheel take it all apart and I do mean all apart, remove everything, springs, friction plates and take the hub that bolts to the crank off, 2 small countersunk screws and remove everything in there also, there are some friction plates in it also.
It might be necessary to cut the big springs with an angle grinder, and pop them all out. Once they were out, you can turn the "inner sanctum" which is still held in place at that point by rubber bushings. Some whacks with a hammer and punch allowed it to turn. Once it rotates about 20 degrees, you will see everything will start to fall apart for you.
The part that the pressure plate bolts to, the clutch plate, has 6 holes in the center that also bolts to the flywheel hub, this hub has 6 blind threaded holes that needs to be drilled all the way through I drilled them out to 3/8 even though they were threaded, I thought 3/8 X 2" fine threaded grade 8 bolts would be the right size and would match the holes in the ring gear plate better. , be careful when removing the hub plate that has the blind threaded holes as it is mounted to a center that is a roller bearing and you might pull the bearing apart.You might have problems getting the center bearing to come off the hub, and experience the loose ball syndrome. If indeed you do pull the bearing apart you will need to put the ball bearings back in as to line up everything. Don't worry about the bearing as it will serve no purpose after you bolt the whole thing together.
If you notice on the plate that has the ring gear, there are 9 holes drilled through it. 6 of the holes are smaller and will almost line up with the 6 in the hub you just drilled, you now have to drill the holes in the ring gear plate to match the ones in the hub you just drilled. I did this by bolting the 2 part hub back together on the ring gear plate so the clutch plate would line up true and then put 3 smaller diameter bolts, 5/16" bolts through every other hole I drilled out in the hub and through the smaller holes in the ring gear plate to line every thing up. I ran a 3/8 drill down to drill out 3 of the holes in the ring gear plate, I then put the 3/8 bolts in the 3 holes I just drilled out and tightened them, then drilled out the other 3 holes. I put all grade 8 bolts in and used lock nuts, but do not use the ones with plastic in them but all metal locknut's, torque the nuts to 40 lbs.
The 9 bolts that bolt the flywheel to the crankshaft also goes through the ring gear plate and the clutch plate, the hub now bolts to the ring gear plate so everything is bolted together to make it a single mass. Use a clutch disk with springs in the center to take some of the shock out of the diesel shut down.
Otherwise, it is easier to understand when your looking at the DMF while reading my notes.
No more noise and you can still use you stock clutch setup with the springs in the clutch hub. Hope this is of some value to you. Let me know if you use this and how you like it.
If you have any questions please fell free to ask.
Once again if your clutch disk dose not have the springs in the center you will need to get one that dose. This is to absorb some of the torque and not twist the center out of the clutch disk and help absorbing the torque shock to the transmission on start up and shut down.
Editors Note: Having done this myself, I would personally recommend that you change your ZF transmission fluid from the recommended ATF, to a streight 30wt. motor oil, overfilled to a total of 2 gallons. This will help decrease the low speed gear rattle that is typical of all SMF conversions.
The "Lucky Mod"
Changing a Dual-Mass to a Single-Mass Flywheel
By Jim Williams (Lucky Larue)
When taking out the flywheel be careful as this thing is heavy, and it weighs around 65lbs.
One thing if for any reason you have any concerns don't try this . This is at your own risk, Mel Agne has done this conversion and so far it has worked out great, I have not put this in my truck as of yet but have it ready as my flywheel is making noise and I have this ready when I do change the clutch out I will change this out also. I am not afraid of using this fix, I feel really safe doing this to my truck.
I strongly suggest you drill out the bolt holes on a GOOD drill press to make sure the holes are straight. It would not be a bad idea to check the balance after putting it back together before installing it.
There is a guy on E-Bay that has made a DMF hub that dose the very same thing I have done and he wants $200 plus shipping for the hub, that is where I got my idea and tore a flywheel apart and discovered this trick This fix will cost you whatever the price of the 6 grade 8, 3/8 X 2" fine threaded bolts & lock nuts and about an hour of your time drilling out the holes and bolting it all back together once you have the flywheel out.
After removing the flywheel take it all apart and I do mean all apart, remove everything, springs, friction plates and take the hub that bolts to the crank off, 2 small countersunk screws and remove everything in there also, there are some friction plates in it also.
It might be necessary to cut the big springs with an angle grinder, and pop them all out. Once they were out, you can turn the "inner sanctum" which is still held in place at that point by rubber bushings. Some whacks with a hammer and punch allowed it to turn. Once it rotates about 20 degrees, you will see everything will start to fall apart for you.
The part that the pressure plate bolts to, the clutch plate, has 6 holes in the center that also bolts to the flywheel hub, this hub has 6 blind threaded holes that needs to be drilled all the way through I drilled them out to 3/8 even though they were threaded, I thought 3/8 X 2" fine threaded grade 8 bolts would be the right size and would match the holes in the ring gear plate better. , be careful when removing the hub plate that has the blind threaded holes as it is mounted to a center that is a roller bearing and you might pull the bearing apart.You might have problems getting the center bearing to come off the hub, and experience the loose ball syndrome. If indeed you do pull the bearing apart you will need to put the ball bearings back in as to line up everything. Don't worry about the bearing as it will serve no purpose after you bolt the whole thing together.
If you notice on the plate that has the ring gear, there are 9 holes drilled through it. 6 of the holes are smaller and will almost line up with the 6 in the hub you just drilled, you now have to drill the holes in the ring gear plate to match the ones in the hub you just drilled. I did this by bolting the 2 part hub back together on the ring gear plate so the clutch plate would line up true and then put 3 smaller diameter bolts, 5/16" bolts through every other hole I drilled out in the hub and through the smaller holes in the ring gear plate to line every thing up. I ran a 3/8 drill down to drill out 3 of the holes in the ring gear plate, I then put the 3/8 bolts in the 3 holes I just drilled out and tightened them, then drilled out the other 3 holes. I put all grade 8 bolts in and used lock nuts, but do not use the ones with plastic in them but all metal locknut's, torque the nuts to 40 lbs.
The 9 bolts that bolt the flywheel to the crankshaft also goes through the ring gear plate and the clutch plate, the hub now bolts to the ring gear plate so everything is bolted together to make it a single mass. Use a clutch disk with springs in the center to take some of the shock out of the diesel shut down.
Otherwise, it is easier to understand when your looking at the DMF while reading my notes.
No more noise and you can still use you stock clutch setup with the springs in the clutch hub. Hope this is of some value to you. Let me know if you use this and how you like it.
If you have any questions please fell free to ask.
Once again if your clutch disk dose not have the springs in the center you will need to get one that dose. This is to absorb some of the torque and not twist the center out of the clutch disk and help absorbing the torque shock to the transmission on start up and shut down.
Editors Note: Having done this myself, I would personally recommend that you change your ZF transmission fluid from the recommended ATF, to a streight 30wt. motor oil, overfilled to a total of 2 gallons. This will help decrease the low speed gear rattle that is typical of all SMF conversions.
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