06-03-2018, 01:09 PM
A few months ago I obtained a late D-type rear axle and overhauled it prior to fitting it to my car. New bearings and seals all round. I set up the CWP adjustment according to Woodrow and everything else I could glean elsewhere.
During the overhaul I found that the pinion shaft had considerable end float and the crown wheel has run-out (sorry, I can't recall the figures for each).
After installing in the car the axle appeared to work well. The only negative thing is a droning noise at a steady 35/40 mph with light throttle. It doesn't happen when accelerating or on trailing throttle.
Can anyone suggest what may be causing this, and point me towards what I should be looking for before I tear it all to pieces again?
I had not driven the axle before I bought it, so I don't know if it made this noise before the overhaul. I suppose it is possible that, if it had previously been used for a long time with the pinion end float, the CWP gears might have worn unnaturally. Perhaps it is the effect of the crown wheel run-out and I shall just have to live with it.
My previous axle didn't make this noise, nor did any of the A7s I have owned before, so I know it is not right.
It would be great if I could adjust the mesh of the CWP and eliminate the noise, but I guess that would be a tricky operation with the axle on the car.
Any suggestions gratefully received!
During the overhaul I found that the pinion shaft had considerable end float and the crown wheel has run-out (sorry, I can't recall the figures for each).
After installing in the car the axle appeared to work well. The only negative thing is a droning noise at a steady 35/40 mph with light throttle. It doesn't happen when accelerating or on trailing throttle.
Can anyone suggest what may be causing this, and point me towards what I should be looking for before I tear it all to pieces again?
I had not driven the axle before I bought it, so I don't know if it made this noise before the overhaul. I suppose it is possible that, if it had previously been used for a long time with the pinion end float, the CWP gears might have worn unnaturally. Perhaps it is the effect of the crown wheel run-out and I shall just have to live with it.
My previous axle didn't make this noise, nor did any of the A7s I have owned before, so I know it is not right.
It would be great if I could adjust the mesh of the CWP and eliminate the noise, but I guess that would be a tricky operation with the axle on the car.
Any suggestions gratefully received!