Rear end seems to be making a bit of noise. Before it was at 80kmh under light load (or coasting), was really loud. I put some oil stabiliser in it, but its still there (though much less). Sounded like it was coming from rear end.
The noise now occurs at basically all speeds at the same frequency, at the same faint volume. Becomes louder upon coasting in higher gear. Noticeable around town if I listen for it. More noticeable going around sharper bends.
What could it be? Diff? Wheel bearings? other drivetrain issue?
A full diff rebuild is uneconomic. Could changing the oil and put some additive in it help?
Ok - scrub that. Noise isn't there all the time, i.e. frequent but intermittent. Sometimes present when vehicle is stationary and idling, so it may not even be drivetrain related.
Another thought - could it be resonance coming from exhaust system?