Hello ,
My searching the archives did not come up with the answer.
Is it normal for the drive shaft to be able to be 'turned' a bit with car engine off and parked on ground ?

I notice that the shaft has a bit of slack at the front flex disc only where the drive shaft connects to the disc. Not where the disc connects to the tranny.
The disc looks OK visually. The bolts seem tight But the drive shaft bolts that connect to the front disc do have a bit of side to side slack within the disc holes. Normal or should they be tight and allowing no movement?

Car has about 136K miles. I'm sure the flex disc has been changed at some point in time before.
Otherwise there is no vibration while the car rides or clunking noise.

What alerted me was a flapping noise periodically when it was put in gear. The noise sounded like plastic paper slapping rotationally but faster than the slow driveline.
That's why I got under to inspect.

Both flex discs look visually OK except for the drive shaft
'slack'. Its about a 1/4 inch or a bit less rotational slack.

Thanks.

__________________
1979 300D 220 K miles
1995 C280 109 K miles
1992 Cadillac Eldorado Touring Coupe 57K miles SOLD
********************
1979 240D 140Kmiles (bought for parents) *SOLD.
SAN FRANCISCO/(*San Diego)
1989 300SE 148 K miles *SOLD

That "slack" you are referring to is normal on all cars....it is there because the parking prawl lock inside the transmission is a toothed gear, so there is a gap between each tooth, thus the drive shaft can turn a little each direction before it hits the stop.

The gas vehicle flex discs do have a bit of "allowed movement" in the bolt holes of the front flex disc. This is to absorb the sudden force that a gasser can put out compared to a diesel.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Thank you very much pawoSD. I feel better now.

I'm dealing with replacing the right rear regulator jaw and happened on this new 'unknown'.

One less thing to worry about.

__________________
1979 300D 220 K miles
1995 C280 109 K miles
1992 Cadillac Eldorado Touring Coupe 57K miles SOLD
********************
1979 240D 140Kmiles (bought for parents) *SOLD.
SAN FRANCISCO/(*San Diego)
1989 300SE 148 K miles *SOLD