How do you keep sliding door from falling off its track of 90 astro van?

Answer 1

I presume you mean the outside track. Most likely, due to the year of your vehicle, your roller bearings are worn out to the point of no longer being able to stay in the track. Get a new set of bearings. Remove the trim covers inside the van where the track runs outside. Remove the right tail light assymbly and the rubber plug you will find behind the tail light. Remove the bolt under the rubber cap. Remove the bolts to the track cover found under the inside trim panels. Remove the bolt at the door latch area that holds the track cover. Remove the track cover, do not force it, just find the bolt you missed.

There are a couple of ways to proceed. I reccommend removing the circlip and driving out the pin that holds the bearing assymbly to the sliding door. Replace the worn bearings and lubricate as needed. Take the bearing assymbly to the rear of the vehicle at the track end and insert the bearing assymbly into the track and run it along the track to the door, then pin it back into the door (a helper, a jack, or any type of door support is useful here). Slide the door along the track to detect ease of operation or other problems. Reinstall track cover, tail light, and interior trim panels.

FYI, some of the interior bolts and the roller assymbly pin are difficult to get to but not impossible. Plug any hole an interior bolt could fall into during removal and installation, have a wobble extension, a magnetic part retriever, spare circlips, and/or spare bolts handy. You might want to use a hole cutter to get to one of the interior bolts.