Hi Y'all,

I have a 1991 F-250 7.3 IDI 4WD ZF5

I recently noticed a shaking coming through my shifter when I depress the clutch in high gear. At first I thought this must be my transmission or motor mounts, but my engine and transmission don't seem to be moving at all when hold the break down while giving it some gas, and no amount of prying of them seems to cause movement.
The video shows this happening when I put the clutch in in 5th gear (the back of the truck is on jack stands) I'm concerned this is an early sign of my DMF going out, since I can't find any other logical reason for the shake. Anyone have any ideas about this? I've never worked on a vehicle with a DMF before and what I've read about them cracking bellhousing has me worried.

I need to do my ball joints this week, and it would be a pretty big blow if the DMF went out not long after I put that money and work into it. I'm trying to figure out if a new flywheel/clutch is going to be needed soon as well, or if this shake is something I don't really need to be too concerned about.

Thanks so much taking the time the read this. Any replies are appreciated!
Jackson

 

pull the inspetion plate off and pry the plate
if it moves, then you know what it is

Shifter moving like that could be input shaft or pocket bearing worn if DMF is ok

 

dmf was a good idea on paper, but a bad idea in the real world. after a few years of abuse, they fall apart.
i had one that fell out of the truck in 4 or 5 pieces after the trans was removed.

 

Hey thanks for much for your replies. I didn't realize I could just pull off the inspection plate.

Knottyrope, I know you said "it if moves, then you know what it is"
I attached a video because there is a little bit of movement with the prybar, but it wants to come right back and feels pretty solidly on there. Is this the kind of movement your talking about?

 

you are moving the flex plate part

Now try to move back n forth the pressure plate while in N and parking brake on

See if it moves too much like in this thread
https://www.ford-trucks.com/forums/9...-complete.html

 

Oh, I see what you mean now.
Looks like I have a whole lot of slop!

Thanks for your time and patience in explaining this to me

 

You are welcome and thanks for posting your vids to help others.

Make sure your input shaft on the trans has no play when you remove it

DMF can ruin that bearing and the pocket bearing goes with it

not bad to rebuild, i have done it before in my garage on a small table