VZ auto slight grinding feeling from rear of car

[Prego]

Update. Diff oil changed. No surprises there. Reversed the trailer up the driveway today but none of the previous grinding. I wouldn't have thought just the oil would be the problem but a cheap option to rule it out. Thanks AdventraAddict for a new option. I'll have a closer look at those.

 

[tezza98]

why would it be the diff oil

i had a noticable knock and grind from the rear when i reversed, a dak dak dak dak whiring sound, changed the diff oil and it has been fine since