190E Diff noise
Thanks for your comments Robby. I'll feel happier with the correct grade of synthetic oil in the diff.
Looks as though I'm stuck with the whine for a while.
As a matter of interest, when I first purchased this 190E 2.3 I had trouble accelerating smoothly.
Found that the throttle butterfly-valve return-spring was missing. Fixed the problem by replacing the spring, which is quite awkward to fit.
Take the distributor top off. This will give you sufficient room to get your left arm in behind the intake manifold, to the point where the spring is anchored. The "free" end can then be connected to the bottom lever on the butterfly valve. Total cost: $3.
Regards, Murray Blackwood.