I have a truck that is used exclusively for farm use. Are the tires and/or other repairs on the truck exempt from sales tax?

No. Tenn. Code Ann. § 67-6-207 specifically provides that a truck is not farm equipment. Since the truck is subject to the sales tax, any tires, replacement parts, and labor performed on the truck are subject to the sales tax. The same answer applies to the trucks and trailers that loggers use to remove harvested timber from the forest.