'77 drivetrain vibration

[Rupesy]

I just started to get some drivetrain vibration between 45 and 60. Above 60, not noticeable and below 45 not noticeable. When I am around 50 mph and I put the clutch in, it still vibrates. I think it might be something amiss in the pumpkin. I decided to drain the rear and I actually didn’t get much out, however, I never noticed a leak. I'm thinking maybe the bearing went since there was very little fluid. Anyway, I attached a pic of what was attached to the drain plug. Looks like a tooth. I recently replaced the driveshaft bearing/bushing and the flex joint looks good so I don’t think they are the culprit.

I have also noticed some chirping noises or noises that sound like two metal plates rubbing together near the transmission area as well. However, the trans shifts fine and clutch works fine as well. I’m not noticing anything unusual there, but I was thinking that maybe I have a pilot bearing issue also.

Any suggestions or comments welcome.

[So Cal Mark]

looks like a piece of a tooth

[majicwrench]

Yup, tiny piece of tooth. That is not likely creating a vibration. When you get that 45-60mph tight vibration, tis almost always driveline related.
Keith

[fiat218]

my 72 did the same thing, vibration at 70 ( i think) then 73 it was gone
i forgot to say, that i replaced all the drive line items , never helped, balance all 4 tires with a rotation
never found that problem

[baltobernie]

When you replaced the driveshaft bearing/pillow block, did you check the universal joints? One of mine had a dry "leg", and after replacing it, the vibration disappeared.

For other owners ... if you're going to the trouble and expense to pull the driveshaft, replace both (inexpensive) U-joints along with the pillow block. And don't forget to mark the driveshaft sections with a paint pen before disassembly, to ensure the factory balance is retained.

[majicwrench]

Fiat 218, high speed vibrations are almost always tire related. Driveling vibrations ( since it spins 3 times faster) are at lower speeds.
Keith

[fiat218]

I don't have the car any more, but I had. The tires balance,rotated in any way possible, never solved it

[Rupesy]

Well it ended up being the rear u-joint. One of the bearings disintegrated. My daughter and I replaced both the u-joints and the vibration is gone.

Car made it one day and then the clutch cable broke! Ahhhhhhhh!

Going to be a new car pretty soon.

Thanks for the help!

[baltobernie]

Glad you got it fixed. Chasing vibrations can be a frustrating experience.

With the old clutch cable out, try starting the engine. The clutch cable will substitute for the electrical ground cable if the original is defective. As you can imagine, this leads to premature clutch cable failure.