I spent a few hours the other day repairing a torn boot on the joint where the angle gear and the driveshaft join up on my V70R [used the kit Volvo offers, this is the second time I've fixed this problem]. I also made sure the angle gear had plenty of fluid.

Before repairing this issue, I was having the same noises caused by this problem in the past [a metallic rattling/tapping noise]. After repairing it, I still have these noises.

I drove the car around afterwards alot to make some observations - The noise occurs most of the time when I am off the gas and cruising to a stop. It feels and sounds fairly normal under acceleration. And when cruising on the freeway I get a slight vibration [feels like it's in the armrest area, the rear tires are balanced fine so that is not it] and I can hear the noise faintly. It does not seem to make the noise in turns [trying to rule out the angle gear]. It most consistently makes the noise when I have it in reverse.

I know my motor mounts are fairly worn and that alone can cause noises, but due to when the noises are occuring I am not 100% sure that is causing it. I replaced the angle gear 15k ago and I put new tires on under 3k ago [my old tires were a bit worn, and the fronts were exactly 2mm difference from the rear in terms of wear]. Might my viscous coupling be bad?

Anyone got any ideas/input on what might be up? Things to check?