So, I finally got around to gathering everything for a spare set of studded snow tires. Thanks to someone for bringing up the TPMS, or I probably wouldn't even know I had until the light came on. I knew it would be a bit of money, but we run winter tires for a long time up here (September through May most years), so I wanted them to be right. Just going to Ford or to a regular tire shop looked painfully expensive, so I got the hardware off of eBay, and the tires from Sam's Club.
Ford OEM Alloy Rims (new in the box...nice wheels) $280 for 4
Used TPMS modules, takeoffs from an Explorer 130 for 4
Mounting kits for TPMS new from Ford 210 for 4
4 Pacemark M&S studded wheels, mounted, balanced
installed.......... 410 for 4
So, for $1000 and a bit, I've got a spare set of wheels.
After about 10 minutes of driving, the TPMS light came on and stayed on until I got home and shut things off. At next start, the light didn't come on, but there was a message on the speedo about tire pressure. At next start, no light and no message. As far as I know, the system is just working, though I don't feel like letting the air out of a tire to find out.
The mounting kits are just a bracket (already on the used modules) and big stainless hose clamp. They would definitely be reusable if anyone found a used set, and is the only place I think I could have saved much money. The Ford dealer had them in stock, and said the tire places are starting to buy a bunch of them........I would guess because the bead breaker on the tire machine probably side punches the module when used by an unwary tire man. When it's time for a tire change you may want to remind the shop you've got a module in yours. I first thought the "180 from the stem" rule was about balance, but I suspect it's more to exactly locate them for the tire guy.
I also picked up the activation tool on eBay for $70, thinking I might need it to make the new modules sync to the car, but I guess not. If anyone needs it, talk to me

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