My 1994 f150 has been parked for years, it won't turn over even with new battery.
You can try and remove the spark plugs and spray a little lubricant in the cylinders, then take a breaker bar with a large socket and try and turn the crank shaft by hand. Leave the plugs out so there is no compression. If you are able to turn it over by hand try using the starter next, then put the plugs back in and start from there.
I know someone who buys a lot of old cars and he uses ATF in the cylinders to loosen them up.
Yup, transmission fluid is good as well as Marvel's Mystery Oil. Let the lubricant sit in the cylinders for a few days. HTH. -Jim
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