Stevethe11th

I just got a 2011 mustang v6 manual with about 102k miles on it and every time I go in excess of 80 miles per hour in 3rd gear after I come down there is a high pitch whine that I think comes from the diff. It almost sounds like something is lose. Could I be shredding a gear in my diff or could this be from the driveshaft which I have heard isn't very reliable. I do drive it kind of hard. I do some first gear pulls at stop lights and such but nothing like tracking it.

Stevethe11th

The previous owner had a full exhaust except headers put in and a bbk cai and maybe a tune but I don't think so.

GT Nate

wonder if the fluid's ever been changed. Supposed to change every 60K

08'MustangDude

So, it does that at 80, in 3rd? How about at 80 while 4th, 5th, 6th? If it's only in
3rd gear, it's not the differential, it's the trans. The drive shaft and diff are rotating at
the same speeds at 80, no matter what gear you are in. So, if you are going 80
and you do not hear the noise in 4th, 5th, or 6th, then it's the transmission's 3rd
gear yelling "Ahhhh, don't go any faster, ahhhhhh!!!"

Gear oil in DIFF is said only to be changed if it became submerged under water, but
change it anyway at 60,000 mile intervals.

Stevethe11th

Stevethe11th

08'MustangDude

I didn't ask WHY you were doing 80 in 3rd gear....

I asked if it does it at 80, in OTHER gears, so let's try this AGAIN:

Okay, so WHERE oh WHERE in that do I ask WHY you were going 80 in 3rd? I
was trying to help you diagnose TRANS or DIFF, and you totally blew that off, and
and gave me an answer I didn't ask for... Then also answered the diff oil change
deal, which was also totally ignored.

Stevethe11th

I said that because I don't really know if it happens in any other gear and I explained why. I only was only in fourth once going that speed and I think it still did it. I didn't say anything about the diff oil because someone else had already commented about it. Sorry if that pissed you off. I'm just trying to get whatever help I can receive. If you would like to explain how I can check if the diff oil needs to be changed, be my guest.

rls82959

Kinda sounds like coast whine in the differential, but would need to check the other gears as coast whine would be in all gears. A fluid change with premium fluid might help with coast whine.

Stevethe11th