On this excellent Aerostar Forum, I have read and understood those of you driving your Aerostars in true winter road conditions, ice, snow, and road salt. I'm in dry, rust free Sacramento, California, but study and understand rust issues from growing up in northeast OHIO. Tip: Saturday afternoon which changing the oil and oil filter on my '87 Aerostar, I had the van up on common ramps, front wheels on the ramp. Laying on my back, gawking, I noticed two rubber plugs that were cracked and brittle. Look for two rubber plugs on the driver side, inner rocker panel area. If you look at the level area that are the front jacking points, directly behind it you will see two rubber plugs, about the size slightly larger than a silver dollar. Mine were cracked, which allowed water into the inside bowels of the lower rocker panels, under the door and back toward the middle frame rail area. I squirted some water in the plug holes, and with the van up in the air, it came out, dripping, down near the gastank filler pipe entry area. Conclusion: If those rubber plugs are cracked, or missing, it will allow road saltwater inside the sheetmetal, which will cause rusting in areas you can't see until it's too late. Those of you in the rustbelt areas, check those rubber plugs the next time you are under your Aerostar. There are two same rubber plugs on the passenger side. I replaced all four plugs, as I had a body plug assortment pack in the garage, from the HELP! line of aftermarket parts. This will keep water from getting inside the Aerostar rocker panels. My van is solid, no rust anywhere since it's never exposed to road salt. Just a tip for my fellow Aerostar drivers in the snowbelt. Ed...

 

Ed,

On my '91 AWD I noticed that inside the box support where it attaches
to the rocker panel there is a small slit that lets water into the rocker
panels. I noticed that when flushing the crud out of that area water was
draining out of the rocker drains. I have had to patch a small area in
front of the rear wheel on the passenger side. I have tried spraying
rust converter inside after flushing and drying to slow down the corrosion.
I am planning a bumper to bumper preventitive maint. campaign soon and
that will include removing the rubber plugs to see what is going on inside
as well as what can be done. I really want to keep the ol'Aerostar running
as long as possible (at least until I can't get parts).