Diff Whine

[Brian]

What causes a diff to whine, and is there a remedy to it? My Triumphs all have diffs which whine ranging from hardly at all to terrible! My PI estate broke two teeth off the crownwheel the other week so I have put a spare diff on. I don\'t know if this whines yet as I have not driven the car.
Thanks,  Brian

[Alan Chatterton]

The whine can occur for several reasons;
a) Knackered nose piece bearings
b) Knackered diff bearings
C) (Most common) The teeth on the crown wheel wear out, the case hardening disappears and the teeth sharpen themsleves on the pinion gear. Caused by excess backlash and or lakc of oil and mileage. No remedy (apart from new CWP as megabucks!)
Find a good s/h diff for about £50-75 and chuck it in after checking the nosepiece bearing. Should be a small amount of up and down movement but not loads, as is usual!
For a good diff try Winns, Triumphland or Mick Papworth (02476 644499)
Rgds
Alan
 

[Brian]

Hello Alan
Thanks for that, I suspected that there was no easy cure! I\'ll try a good secondhand one. What gear oil do you reccomend? Is synthetic suitable in the diff, or is it best to stick to normal EP 90?
Thanks,  Brian

[Alan Chatterton]

Stick to EP90. Best stuff for the job. Make sure when you get another diff that you always change the diff nose seal. Takes 10 minutes, costs about £15.00 but ensures that the new oil stays in!
Rgds
Alan
 

[Clifford Pope]

Just make sure that it really is the diff causing the whine, and not the gearbox. IME noise travels along the propshaft and it is sometimes very difficult to pinpoint the source.
<br>The diff quill extension bearing is a good one to check first, because you can withdraw it from the diff and spin it by hand without having to take out the whole diff.

[Brian]

Thanks Clifford
I\'d automatically assumed that it was the diff because the noise seems to come from the back. I\'ll try running it with the propshaft disconnected from the box and see what happens
Rgds&nbsp;&nbsp; Brian&nbsp;