89 F-250 dual mass flywheel question.

[kellyf]

This truck is a little before my time.In between shifts,sometimes a very loud thud,knock noise be heard.Sounds like it is coming from around the tran area.A pretty knowledgable guy in the shop thinks it may be the dual mass flywheel springs making a noise.I have heard of some dual mass flywheel issues,but do not have any material to back them up.He also said there was a problem with some kind of rivit breaking on the frame,but that appears ok.Thanks for your time.

[Bruce Amacker]

This truck is a little before my time.In between shifts,sometimes a very loud thud,knock noise be heard.Sounds like it is coming from around the tran area.A pretty knowledgeable guy in the shop thinks it may be the dual mass flywheel springs making a noise.I have heard of some dual mass flywheel issues,but do not have any material to back them up.He also said there was a problem with some kind of rivet breaking on the frame,but that appears ok.Thanks for your time.

Done lots of DMF's in my life, never had one make the noise you describe. Shakes and chatters, but never a loud thunk. Ask the owner if anything has been done to it, on that old of a truck it may have already been replaced (SMF installed).

 

Yes, it could be the DMF. I don't know anything about the frame rivet.

 

Use a Luk single mass update if you change it, he'll love it. It comes with the flywheel and clutch assy and it cheaper than buying a DMF from Ford.

 

Good Luck!

 

[Keith Browning]

If I can recall correctly, there was a TSB on removing one or more huck-rivets at the engine crossmember and replacing them with bolts. The loose fastener would create a heavy clunk or snap in the frame during certain turns. A heavy structural noise will travel... you might think it's coming from the floorboard when sitting in the drivers seat.

 

I have attached the two TSB's below.

[kellyf]

Thanks Keith.We got to looking and found there is an ominous leak from the transfer case.If you put in 4 high starts raising hell.