Up here in Canada,.....
 

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We never said "Zee 28" it was always "Zed 28"


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But luckily we never said "Zed Zed Top" that would have been embarrassing.

Ha!
First time I ever heard the term I was at an antique tractor show in Ontario. A guy told me, "My dad bought that Zed over there new in 1938. Been farming with it ever since." I thought I he was talking about some rare Canadian tractor that I had never heard of. Turns out he was talking about a Minneapolis-Moline model Z.

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We call the Z28 a Zedder, doesn't work so well as a zee-er.