Rear differential question

[Turdle]

Boy, did this thread go off topic!

Install the fluid. If you notice a chattering feel from the rear during a turn, add 1/2 bottle of friction modifier.

 

[R1dd1cK]

Thanks!

Didn't mean to start an argument I know the door hasn't been replaced so the sticker should be factory. Guess I'll find out for sure when I pull the diff cover.

Yea some people just get to defensive. Every explorer I have worked on the door sticker was right. Even the ones I looked at at the junk yards. But with that said there is still a chance it could be wrong. Who knows what could have been done before owned it. Like for an example. My v8 4406 swapped sport. It came with 4.10 open diffs. It got a 4.10 limited slip swapped in. It acted just as bad and the open diff did. I mean you couldn't tell it was different. So I rebuilt it with a ford racing cobra clutches. I must say I couldn't be happier with it now. So the only sure way to know is going to be pulling the diff cover.

 

[deweyville65]

May be defensive. But I don't like being told I do not know what I am talking about when I have operated the equipment for years. Some people either do not understand what they read. or have no idea what they are being told. Enough said.

 

[swshawaii]

Only posting this because it's relevant to this thread. There have been many more that were almost always edited after the fact. (Reply #4 in this thread)

However, if you use the Mobil 1 75W140 LS fluid, it already has the friction modifier additive in it - read the description.
Only the Motorcraft fluid needs it.

Post #9 from 11/1/13

You need the friction modifier additive if you have limited slip. That's what the owner manual says, trust it. Mobile 1 is great, but doesn't have the LS additive, because is not needed in other applications (open diff for example).

http://www.explorerforum.com/forums/showthread.php?t=395985

 

[masospaghetti]

All synthetic gear oils i've seen already have the LS additive, only the conventional ones do not. Not sure if this is a hard rule or just common practice.

Interestingly, a local 4x4 shop recommends conventional 75w-140 instead of the synthetic oil in the rear end, they claim it provides better protection for the bearings.

 

[SoNic67]

I am not aware of any conventional oil 75W-140.

However, adding a $8 bottle of LS additive in it, can't do anything bad...

 

[masospaghetti]

It may have been 80w-140 for conventional.