I had to replace the front right wheel bearing due to a droning sound. However my mechanic has now stated that the carrier bearing on the right drive shaft needs replacing

He said he put a scope on it and found out it was failing. To be fair there is a droning sound which gets louder when you go faster. Is this normal as there is only 89500 miles on it

So basically wrongly diagnosed. No suprise. 

The driveshaft support bearing is a common failure. Easy and quick job to do. 

Hi. Further to my post regarding the drive shaft bearing. I have changed both the right wheel bearing and the carrier bearing.( I take it that is on the drivers side of the drive shaft ? )  however the noise still persists. I'm now thinking it might be the tyres. I checked them and they seem to be the wrong size for the model year. Mine are 215/50 R17 95w.Psi 33. Do you think it might be the tyre pressure?

215/50/17 is correct for a Mk3 Zetec.  Pressures should be 31psi all round for normal load.  But the extra 2 psi is unlikely to be causing the noise.

As it's a 1.6 TDCI, it's likely to be a gearbox bearing failing.  Though it would be worth swapping wheels & tyres front to rear to see if the noise changes first.

 

I have changed the wheels from front to back as requested but still the noise persists. I'm at my wits end. Only starts when you do over 50. 

That's a shame.  It could well be gearbox or diff related then.  Not uncommon on the Mk3 1.6 TDCI.  If you have any local transmission specialists, it might be worth asking their opinion.

Ok. Am taking it to the garage now. Will keep you informed 

The mechanic is looking at the possible causes of the droning noise. However a long shot. But could the fan belt or drive belt coming loose cause it. Don't have any problems with tje alternator or anything else. Just a thought

Not really.  Aux belts squeal when they slip.  And they move at engine speed, not road speed, so it would be repeatable when stationary.  The belt on 1.6 TDCI is very small.  It only drives the alternator and AC compressor.  The belt auto-tensioner bearing can drone, but again that's still related to engine speed not road speed.

A drone at road speed has to be between the diff and the tyre.  Or being caused by airflow over the bodywork.

Thank  Tom. very much appreciated. I will keep you inform3d fir future ref. Cheers

I have finally found the problem. It transpired it was the passenger side wheel bearing after all. It's now perfect. The other repairs trying to find it had to be done any way. But I now have peace of mind. Thank you for your time.