(a) It is a violation of this act for a farm equipment manufacturer to coerce, or attempt to coerce, any farm equipment dealer to accept delivery of any farm equipment, parts or accessories therefor, which the farm equipment dealer has not voluntarily ordered.

(b) It is a violation of this act for a farm equipment manufacturer: (1) To condition, or attempt to condition, the sale of any farm equipment on a requirement that the farm equipment dealer also purchase other goods or services; except that nothing herein shall prohibit a farm equipment manufacturer from requiring the dealer to purchase all parts reasonably necessary to maintain the quality of operation in the field of any farm equipment used in such dealer’s trade area; (2) to coerce or attempt to coerce any farm equipment dealer into a refusal to purchase the farm equipment manufactured by another farm equipment manufacturer; or (3) to discriminate in the prices charged for farm equipment of like grade and quality sold by the farm equipment manufacturer to similarly situated farm equipment dealers, except that nothing herein shall prevent differentials which make only due allowance for differences in the cost of manufacture, sale or delivery resulting from the differing methods or quantities in which such farm equipment is sold or delivered, by the farm equipment manufacturer.