Subaru offers a rear differential protector for their cars.. how important is that? how do you know when your differential is damaged? How do you know when it's not working??

 

If you don't go off-roading, it's not necessary.

BTW I have a used one for sale!

 

they make a nice flat surface for jacking up your car.

 

Oh yes that's true.

 

You know your differential is damaged when you see it leaking a lot of fluid

OR

Making a lot of noise

OR

Your rear end starts handling erratically

OR

You jack up the rear end, and rotate one wheel, and the other doesn't rotate the same direction. (The rear end of a WRX has an LSD, limited-slip diff, they rotate the same direction). On a car with an open diff (or broken LSD) the other wheel will rotate the opposite direction, or not rotate at all.

AND

Jacking up your rear end is pretty damn easy without a diff protector!!!

ALSO

Diff protectors sometimes hit aftermarket exhausts....

 

A block of wood and a shop towel under the diff.

That's why mine is forsale. Not enough clearance for my Borla Hush.

 

yeah i have an extra one sitting in my garage

its pretty beat up though, got put through plenty of use