4th gen rear differential fluid change

[matsavol]

My 2006 explorer (with slightly less than 60K miles) still has its original rear differential fluid. I have been thinking of changing the fluid and today got to a point to evaluate the current fluid condition. I removed the fill plug and slight amount of very clear and fresh smelling gear oil came out... Just like what I would expect a new fluid look like. This totally surprised me and I'm rethinking of the need to change the fluid?

I guess since this has open differential there is less wear and resulting contaminants than typical (older gens) limited slip. If there was some metal shavings I would not see those at the top of the fluid, but over time I expect those to be ground up to "dust" and dissolved to the oil coloring it dark. Do the oil drain plug has a magnet to collect the metal shavings?

My explorer has never towed anything and it has not been ride through high waters.

 

[USMCBuckWild]

At 60k I would change it anyways. I would be willing to bet that when you drain it there will be some discolored fluid coming out. I do all my diffs at 30k with synthetic fluid, just to be on the safe side. The lower plug has a magnet on it and mine was covered in a thick paste of material. Took me a few minutes to get it clean.

2 quarts of gear oil - $30
New rear diff - $650

 

[Dag06XLT]

There is no age limit (within reason) with diff fluid. You have open diffs so no clutches to worry about clean fluid and additive. Do you HAVE to change it - no not with your miles. Changing it now would be for Piece of Mind, not necessity. If it came out clear, leave until 90K and spend the money elsewhere.

 

[matsavol]

I'm going to leave it alone for now. I'll look at it again after couple years if I still have this vehicle.