My 2 cents from personal reasoning. I could be wrong but haven't seen anything yet to convince me that I am. All electric radiator fans are "puller" when mounted on the engine side and "pusher" when mounted on the grill side. They turn the same direction either way AND the motor restricts air flow whether in front or in back of the radiator. A LOT of people say "puller" fans work better but I've never seen any empirical evidence to prove that. All I've seen is anecdotal evidence. Even googling it only returns personal opinions with no supporting evidence. IMHO put the fan where it works best for your application.

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