benscab

hi all, im new to the forum and would really appreciate some help. i ahve a ford focus estate 1.8 diesel 2002 (02 plate).
when i bought the car it needed a gearbox, so got one from the breakers yard and had it fitted. i then noticed a slight grinding noise ( constant regardless of clutch in/out, and gear engeged /not.). took it to NATIONAL TYRES for a diagnosis and they said could be the wheel bearing on drivers side front. had that changed and noise still there, national tyres then said " there was a score mark on the hub when we took it off, but we thought it would be ok. they then reluctantly agreed to change the wheel bearing under warranty if i paid for a new hub. they fitted both this morning, and lo and behold............. the noise is still there !!! they now say it is probably the diff bearing ? what is this diff bearing and how easy is it to change, also is their diagnosis correct ? any assistance on this matter would be very much appreciated, as its a lovely car to drive ( apart from this noise ).

thankyou in anticipation of your help.
ben.

phil_focus

does the grinding noise change with vehicle speed?

benscab

not too sure, i think it does yes. not really had much chance to drive it other than round town since i got it.

phil_focus

could be drive shaft related.

has the box been filled with the correct amount of oil and grade? should be 2l of 75w90 iirc. might be worth draining out whatever is in there (checking for metal particles) and refill with new. euro car parts sell the right stuff and its free delivery off their website too.

benscab

as far as i know its correct. we went to a car parts shop and they gave us the oil and said 1.91 litres, so just under 2 bottles. but cant remember what grade it was.