I have a 1994 GMC Safari, which is basically the same as an Astro Van. My rig came without the original GM tire key to raise and lower the hoist. I searched online and browsed scrap yards and these things are hard to locate. The very few I did find were on eBay auctions and were way too expensive for such a simple part.
You can find them for 1995 and newer models very easily as these are all standard and common. Apparently the older ones are different however. I assumed I would have to search for a long time or eventually remove and replace the hoist. I even bought a compressor and a bunch of tire plugs and literally fixed 3 flats on backroads without touching the spare.
I ordered new BF Goodrich All Terrain tires for the Safari van and picked up a full size spare. Time to fight this thing. I planned for a full day of wrestling the spare tire with the potential outcome of cutting the cable and starting fresh.
After another round of digging through the internet, I found very little and no clear information. One forum post said you can stick a large flathead screwdriver in the slot and turn it to lower your spare tire hoist. Another mentioned turning the rod itself with a pair of vice grips.
I crawled under the car, fully expecting the rusted hoist to stick and require multiple rounds of penetrating spray to loosen but the vice grips immediately turned the rod and lowered the old spare. The new spare slid right on and it pulled up tight with a few more turns in the opposite direction.
So, if you can’t find a spare tire key, try turning the rod with a pair of vice grips as a quick and easy solution to changing out your spare tire on an older model GMC Safari van, Astro van or other GM model. It could work on other brand vehicles as well.