Rear diff whine

Hearing a tiny bit of rear diff whine at approximately 58-61 miles an hour. Below 58 it’s silent, above 61 it’s silent. The only time you car hear it is while on the gas going 58-61 miles an hour. It’s not necessarily loud but I can definitely hear it over my 3 inch exhaust if I have the music down. Is this something I should be concerned about? Car is lowered and I know that can sometimes change vibration noises and such but don’t think that would cause this


On a side note also getting some ticking noise when accelerating, usually only for the first 1000 rpms of 2nd gear but sometimes when just coasting. I got under the car and shook the drive shaft around and it seems solid, transfer case mounts could be shot though, hard to tell. It sounds like it’s coming from right under the trans tunnel. You can’t feel it in any way, you can just hear it

 

Have you checked or changed the fluid?

 

Just finished changing it (what a pain in the ass to refill) the fluid was definitely super dirty and old, likely never changed, but no metal or debris in it. Just dirty old oil. The whine is definitely quieter but not absent

 

Might just be old and need a rebuild now.

 

What are the costs associated with that. Is it cheapsr to get a whole new diff to swap in or rebuild my current one

 

I would not know. Give Damond Motorsports a call. They have a MS6 racecar and can help.

 

I wouldn't worry about a light whine at cruising speeds. Probably just a little bit of wear on the gears making noise - won't hurt anything.

When something breaks in the rear diff, it causes some really nasty behavior and can get pretty loud.