My 1997 F350 4x4 (107,000 miles, 5 spd) developed a heavy vibration while driving cross country last night. The symptoms are most severe at low and high rpms. They moderate but are still present at 65 mph. The vibration is also present while stationary. The truck visibly shakes. I suspect the clutch is going out but there did not seem to be any slippage. Any ideas?

 

Where is the noise coming from the tranny or the engine?

 

Not really any noise, just severe vibration. It was severe enough to have it towed the 75 miles to my house last night. It seems to be coming from the engine area but I can feel the vibration when I put my hand on the shifter lever.

 

Any codes? And how is the vibration when you sitting still and rev it up a little does it get worse?

 

DMF coming apart? Do you have any mods to the truck? Ohh and welcome to FTE!

Red

 

At idle it runs rough, when i rev to 1500 rpm's there is a horrible vibration/shudder.
No codes as of yet.

 

No modifications to the truck. I have owned it since it was new.

 

I would look at your flywheel I agree with red

 

Does it clunk when you shut it off?

Red

 

No clunk when I shut it down.

 

Sounds like DMF going to me, I had very similar symptoms when mine went. Remove the inspection cover that covers the flywheel, very easy to remove. this is a pic of what I found in the bottom of mine.


This is where the parts came from, The missing parts causes severe vibration due to the out of balance flywheel.


It is not a very good Idea to drive very far with this problem, possible for the flywheel to come apart and that could cause severe carnage.

 

Transmission is cracked from near starter motor to top of transmission.

 

Is it for sure the trans thats carcked? Is it leaking Oil from the crack?

 

It is in the bellhousing area - about a 16 inch crack.

 

That's good it not the tranny. Did you remove the inspection cover yet? You need to do that, but it really sounds like a flywheel/clutch has done the damage.