Yes, you can.
You can but your speedometer will be off. I would use 205/60-15 instead.
Yes you can
Yes, you can
no you cannot
Yes, you can.
Yes, you can.
You can use 205 but your speedometer which will be off. Handling ride and steering will also be adversely affected. Stick with the original equipment size. Plus, you will need 15 inch rims instead of 16 inch. I actually misread your question and did not notice you were wanting to install a 15" tire. In that case you should install a 235/60-15 tire on 15" wheels which is an almost perfect swap and will work well.
Yes, you can use a 235/65R16 tire instead of a 235/70R16 on your 1997 Ford F-150, but there are some considerations. The 235/65R16 is shorter in overall diameter, which may affect your speedometer accuracy, handling, and ground clearance. It's advisable to consult your vehicle's manual or a tire professional to ensure compatibility and safety.
Yes, as long as they are the same rim size. Please always give the WHOLE number of tire size.
No, get a tire shop to check first.
I have a 1999 blazer. The heater core clogs up about once a year from the Dexcool. Try having it (heater core) flushed and use Prestone (Extended life) instead of Texaco.
Yes you can use 205 60 r 16 tires in place of 205 50 r 16. They are only slightly higher.