mirrael

my 2005 c230 kom sound like a have a bad rear wheel bearing 40- 50 miles and increasing , what oil use the diff ? maybe is low

NegroC230

check your tires first, might be out of alignment and therefore cut and make noise. I changed to Red Line 75W90, but owners manual tells you exact weight.

Glyn M Ruck

Run your hand counter rotation over the rear tyres to see if you can feel any feathering or cupping. Tyres can sound like wheel bearings failing on these cars.

If it is the axle making the noise it's too late & repair will be required. Does the sound change from trailing throttle to acceleration? If so pinion bearings have lost preload. If not & it's not tyres then it's diff carrier bearings or wheel bearings. Rear Axle oil does not lubricate wheel bearings.

Use only axle oils with MB approval 235.6 or 235.7 - Benz only approve one additive technology for their axles never mind what brand. DO NOT use non approved products.

BF_JC230

And they smell "Oh so good!"