David = I'm confused with Charlie's answer, so just to make sure it's clear. The answer to your question is "No", the serial numbers for 169's were not consecutive. The serial numbers for all the models ran consecutive as they came down the line. So if a 129 was built right behind a 169 it got the next serial number.
Now, I don't recall how we know the very 1st 169 built is Serial Number 506737, and owned by Thurmond Swafford, but I'll attach a pic of his Serial Number tag so you can see it shows 2050048U506737. The Kind Code is 205 (as it is for all Cub Cadets). The Machine or Model Code is 0048.
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And just so you can tell the serial numbers are not consecutive, my 169 is Serial Number 523760. I'll also attach a pic of it below so you can see the Serial Number 523760, the Kind Code 205, and the Machine/Model Code 0048. (If the 169's were all consecutive serial numbers mine would be the 17,023 one built after Thurmond's but we know IH didn't built that many - so it proves the 169's don't have consecutive serial numbers). Sure wish my tag wasn't all scratched up, but heck, when you find a machine at the junk yard you gotta take what you can get.
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And for what it's worth, my son's 169 is Serial Number 523764, so it's the 4th Cub Cadet built after my 169. No way to know what models the 3 built in between were, but I do wonder if his is the next 169 built after mine. Here's a pic of his tag.
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