I do notice now that they say the vibration damper cannot be interchanged, but they don't say that for the flywheel. They also say that the differences are not discernable, unlike for the damper.

To me it seems that if the differences are not even visible and it fits on the same transmission and engine mounting it shouldn't make a big difference, but the 3D dynamic physics engineering they did to create it are beyond me... that's why I switched to mining!

Jayme, have you brought your engine to speed while in neutral? Seems to me if the engine was unbalanced it should vibrate even in neutral, since the damper and flywheel are spinning.

 

I bet they mean not decernable visually by the average mechanic.

Good idea, ND! If this is done with the clutch in & in gear, then the clutch disk and trans input shaft wouldn't be spinning, thereby eliminating them from the equation. If you don't have the vibration in that condition, put it in neutral & let out the clutch. If the vibration appears, then it's in the clutch disk or front of the trans. Did you install a new pilot bearing?

As far as other parts to change, I always put a new throw-out bearing in. Mr. Murphy is my personal guardian angel, and he makes sure that if I don't, it goes out within a week of my putting it back together...

Let us know what you find out from Ford & Sachs.

Phy

 

Jamye, did you use the original dual mass flywheel off of the 91, or did you use a single mass conversion? If you used the one off of the 91 it could be crapping out, and giving you the vibration you are seeing. This happened on my 97 Stroke, and it cost me a tranny as the bell cracked from the vibration.

 

Honestly i don't know the difference between dual mass and single. The PO of the 91 had a new clutch and throw out bearing installed 7000 miles before i got it. I put 3000 miles on it before parting it out due to registration issues. There fore i just swapped everything thinking i should be ok. And no did not install a new pilot bearing. Also if i am sitting still clutch in and in gear or in neutral and rev to 2500 i get just a very very little bit of vibration that isn't really even noticeable.

 

Just talked to ford, they said there is a difference, the 94 factory turbo calls for a dual mass and he wants $1400. He said i can go after market and switch to a single. Why is that flywheel over a grand more than oriely's

 

If the vibration was because of the flywheel, it should've been just as bad when sitting still & reving...
Did you try sitting still & reving with the trans in neutral and the clutch out? If the vibration comes back under those circumstances then the issue is with the clutch disk or trans. A worn pilot bearing could let the clutch disk & trans input shaft be enough off-center from the crank to cause a lot of vibration...
'Cause it's from the Stealership?? :-)

Probably 3 reasons:
1. It was a low volumn production.
2. It a dual-mass flywheel.
3. It comes from the Stealership.

 

These are from NAPA, the first is a dual mass, the second is a single mass. The dual mass is a two piece design held together with springs and a bearing. It is susposed to dampen the impulses from the diesel detenating by the springs in between the two pieces. The single mas is a one piece design like used on a gasser. The springs are in the clutch plate hub. The 1000 dollar difference in price is why most change to the single mass set up when those dual mass ones go to pot. https://napaonline.com/Catalog/Catal...+50028+2028028 https://napaonline.com/Catalog/Catal...+50028+2028028

 

For some reason i am just getting this, i guess i don't understand the parts. I thought the flywheel was the metal disk with all teeth on it that is bolted to the back of the motor with nine bolts and what the starter engages to go turn over the motor upon starting. This whole two piece with springs and bearings and what not has got me confused. Is the clutch and flywheel together all one setup. Also after crawling around under the truck some more shaking stuff i noticed some place in the tail shaft on the t-case and wondering if this is where my vibration is coming from. A while back my carrier bearing came lose and caused some extremely bad vibrations and i think this my have damaged the t-case.
phy. Yes i did also let the clutch in neutral and it was the same result. very very little vibration at 2500rpm.

 

You are right on what the flywheel is. The dual mass has 2 pieces engineered into one piece, in my opinion not a good design. I will not install a dual mass when they go bad. You still have a seperate clutch and pressure plate with both set ups.
If you look at the back side of both flywheels in the two links above you can see the difference with the springs in the dual mass.

 

for some reason i cant open those pages, just brings up errors

 

check here for a little explanation on dual mass flywheels:
Capitol Clutch and Brake, Inc.

 

That pretty well eliminates the flywheel & clutch as the cause...

 

What about pilot bearing or throw out bearing? if it is not these i think i will throw in my spare t-case this week and see if that helps.

 

You need to change the flywheel from the donor truck's orginal N/A one to a Turbo-Specific one.

Flywheel:
Heavier engine components change the engine balance and require use of a turbo specific flywheel for manual and auto trannys.

Manual flywheel part number is F3TZ6375A
Automatic Flywheel number is 1816637C1

The part's are actually discontinued. So your going to have to find a used one.

You also have to find out if it's the original dual mass flywheel or it's been converted to a single mass flywheel. DMF's DO NOT like engine modification's. They are designed to work at factory setting's only.

 

When you pull it apart, you'll be able to see the differences between Dual Mass and Single Mass:

Dual:


Single:


As you can tell, the Single is much thinner then the Dual. The only way to tell which setup you have is to just pull it apart.