High pitched hum
 

My '70 is developing an intermittent high pitch hum. It's not a squeal. It is drive line related not rpm related. Doesn't matter what gear it's in (3 speed manual) or if the clutch is in or out. Doesn't do it under acceleration. More often hear it when slowing down. Front wheel bearings are good. Iam wondering about drive shaft bearings or u joint. Any input would be appreciated.

Re: High pitched hum
 

Any vibration with the hum?

Re: High pitched hum
 

Check the fluid in the differential. I had a leaky cover and when the fluid got low it would make noise, most notably when at low speed or decelerating.

Re: High pitched hum
 

No vibration. I know the differential was full a year ago and I haven't seen any leaks, but will check that and the transmission.

Re: High pitched hum
 

Typically if the noise is only under deceleration, it signals a problem with the differential.

Re: High pitched hum
 

Could be Neil Young.

Re: High pitched hum
 

x2

Re: High pitched hum
 

For the cost involved I'd replace the 3 u-joints and steady/carrier bearing. If the noise still persists then I go into the diff.

Re: High pitched hum
 

:lol: :mm:


I agree with 70Stovebolt