hello i just bought a 1997 f150 the guy told me it over heats on the high way but is fine on back roads. he also said it may need a new motor.....i really hope thats not the problem.

my question is where should i start looking and tinkering.....water pump?

 

Flush the cooling system and replace the T-Stat. If the truck still over heats then look into the water pump.