It's been an expensive last few days of Astro ownership. I have been working to get the van ready for a family vacation. In the last couple of weeks, I have:
Replaced side mirrors with new late style (early not available);
Changed oil;
Fixed right side exhaust leak (remove manifold, belt sand flat, replace two broken studs from removing manifold, install manifold gaskets);
Replaced wiper blades;
Replaced rear shoes and wheel cylinders;
Serviced AC (receiver-dryer, low pressure side switch, ...and compressor.)
Because I am low on time (leaving tomorrow morning for Florida,) I had a friend do the rear brakes and AC. We are replacing the compressor because the pulley is singing. Might as well, but that compressor is a real chore.
The differential was low on oil and the axle seals had a bunch of gunk built up around them. It is uncertain how fast they leak/how long they have been leaking. It is possible that nobody ever checked the differential oil, in which case the leakage is from the past 37 years and probably isn't an issue. It is also possible that the oil was checked and filled a year ago and that the seals leak profusely. Because I don't know yet which is the case, I'm going to have to take another vehicle to Florida--and I'm bummed about that like you wouldn't believe.
If the axle seals only seep slowly or not at all, I will probably let that dog lie. If they are leaking, I think I will go buy a steel spring style junkyard axle (probably a G80 since the price is the same,) have that rebuilt, and do the steel spring conversion.