How hard are Diff seals to do yourself?

I was just adding Permatex the crud out of those out differential gaskets while you have it apart.

I love that permatex aviation gasket sealer.

 

Make sure the rear end vent isn't plugged up or you will be doing it a 3rd time.

 

that and make sure the driveline is running in balance. If it was just done a year ago and leaking again, something is likely up that’s causing the seal to leak, because those usually last a hell of a lot longer than that if everything is running right.

 

Drivelines slightly out of balance can also cause headaches like this. It will tell on it somewhere.

 

Ford makes some bad ### stuff too. The grey stuff they use to seal the pan on a 7.3 engine.