Gear whine after rear diff fluid change.

[midnightlaundry]

I changed out the Supertech with Amsoil Sever Gear. It quieted it down a little, but it did not eliminate it. Really tho, the noise isn't that loud, it's just noticeable.

A side note is that I only had about 700 miles on the Supertech, and it was a cloudy gray when I drained it. I guess it flushed out the rest of the buildup from the original oil fill.

I'm not worried about a failure tho, because I don't drive the vehicle hard, so I'm sure it will be fine. $37 bux for 2 quarts of that Amsoil oil tho. It's expensive stuff!

 

[racin4ds]

Our 02 Explorer whines too, I've researched it and it seems normal for many of these vehicles and unless you do a full rebuild it won't go away.

I just bought two quarts of Supertech 75W-140 to do a change in mine but have held off because I have an axle seal leaking so I want to change that first. I might go in and have a look while I'm under there.

 

[midnightlaundry]

Yeah, the new clean fluid will leak even worse.

BTW, there's a TSB on that diff that requires an extra 8oz of fluid after the fill hole. That means you can just put in 2 quarts at the ABS sensor hole and call it done.

Best of luck.

 

[stchman]

Originally Posted By: midnightlaundry
I have a 2002 Explorer with an independent rear differential. I replaced the original fluid with Supertech 75W-140. Now I get a little gear while. It's not super loud, but it's noticeable now.

Even tho the grade is the same on paper, do you think a name brand would eliminate the whine? Valvoline SynPower, Mobil-1 and Royal Purple Max Gear are readily available where I live. These all have the friction modifier already in the bottle. I had to add a bottle of the Ford XL-3 with the Supertech.

Any advice would be appreciated.


Is that a limited slip differential?

If yes, did you add the LS friction modifier? If no, that could cause the rear end noise.

 

[midnightlaundry]

LSA is so the clutch packs in the diff don't chatter when going around corners. It has nothing to do with the lubrication of the gears. But yes, I did with the Supertech. The Amsoil has LSA already in it.

 

[racin4ds]

The Limited slip additive isn't necessary either.. I don't run any in my F150 with the ford factory clutch pack diff. It works just fine and actually gives you better locker performance for off road. Very rarely will I even notice any kind of "chatter" when turning sharp.

 

[stchman]

Originally Posted By: racin4ds
The Limited slip additive isn't necessary either.. I don't run any in my F150 with the ford factory clutch pack diff. It works just fine and actually gives you better locker performance for off road. Very rarely will I even notice any kind of "chatter" when turning sharp.


Probably because a lot of modern gear oils already have the limited slip additive included.