2007 Forester Rear Differential Leak

skierjoe

I just brought my 2007 Forester in for an oil change at 20000 miles and received a warning that my rear differential seal was sweating. Should I have the differential fluid changed? I noticed that the manual that it should be changed under severe driving conditions at 15000 miles. Should I consider a synthetic fluid? How difficult is it to change yourself?

xwesx

It is incredibly easy to change yourself, but I recommend that you use a hand pump to put the new lube in, as it would be rather awkward to try and pour something. Synthetic would be a good move, and it could also extend your drain interval significantly (depending on the brand/quality you use).

If the seal is "sweating" though, it will likely only get worse. You should get that fixed under warranty.

ateixeira

I agree, changing diff fluid is not difficult, but that will not address the seal.

So I'd remove and replace the cover to replace that seal. You'll still need the hand pump wes recommends, the local auto parts stores have them for less than $10. Should take about a quart of gear oil.

aatherton

> ... 2007 Forester... at 20000 miles... Should I have the differential fluid changed?
> I noticed that the manual that it should be changed under severe driving conditions
> at 15000 miles. Should I consider a synthetic fluid? How difficult is it to change
> yourself?

For my 2008 automatic, I just changed my front and rear differential oil at 13,000 miles of easy driving. The front oil was amber and the magnet had a light coating of black. The rear oil was gray and the magnet had a thick coating of black. I think the rear should be changed often, and synthetic used. It is easy to change the oil, but it takes special tools for both front and rear, and there are a few tips to know.