Unlike my Forester's (98) front axles, there is no pin holding the axle on the shafter coming out of the differential. So does it just slide off if I give it a pull or is there something else I must do to remove it? The wheel end of the axle would of course have already been removed from the hub.

 

Also, Napa says they have left and right rear axles in their database but just a left one in stock. What is the difference between left and right axles? Can one use a left axle on the right side?

The axles are symmetric. If there is no pin like the front axles, then all you have to do is yank on the shaft. If it won't give with a mild tug, then you need to use a prybar to force the end of the CV housing off the diff. But make sure you leverage the prybar on a bolt head since the aluminum diff side cover cracks easily.

 

There is a circlip on the end of the shaft that goes inside the diff. This is what you are trying to overcome (and watch for ).

i agree with above method. i always just stick a pryparbehind the axle and rest it on a bolt head on the flange and give it a quick pop.