Hello, I am Henry.I have been a Volvo V70 driver for 30 years. Now I have a problem with my 1972 V70.
After driving for about an hour there starts a whining sound. The sound, not very loud, runs in sync with the revs of the engine ( a D5 diesel ) Low revs low sound,when engin revs up, sound revs up.....
Anyone any ideas what this could be ?? Thanks !

 

My V70-D5 is from 2002 and NOT from 1972. Sorry !!

 

Have you tried listening around the accessory belt area - could be something like the AC compressor, an idler, power steering pump or alternator. Do you hear it when revving the engine in neutral?

 

Thank you for your reaction. Yes, the whining sound is also there when revving the engine in neutral .

 

One more thing I noticed is that the whining sound is not there immediately but starts after 8 à 10 miles .