Another serial # question

Just picked up what I thought was a four cyl 2000. Serial# is 125856 which shows to be a 601 but above the serial # it has 660. This has me confused as I would think it
should be 661. It is a five speed with two stage clutch. Can any one explain this? It has the 2000 hood but that could have been changed.

They started the serial numbers over when they switched form the hundred series to the '01 series and again when they came out with the 4 cylinder 2000/4000 series, and then again in 1965 when they came out with the 3 cylinder models.

If it is a 4 cylinder 2000 with a 125856 serial number then it would be a 1964 or possibly a 1965 tractor. They did continue to make the earlier models in special order batches for a while after the new models cam out for the 1965 model year so it may even be from a few years later. The 4 cylinder 2000 offset was made the longest, up until close to the time that the 1710 offset came out in the early '80's because people demanded an offset and Ford didn't have a 3 cylinder thousand series or x600 series offset model so they made the 2000 offset every couple of years in small batches to satisfy the demand, and they continued on with the 4 cylinder 2000/4000 serial numbers for the duration and never used the serial numbers from the 3 cylinder series on those older style machines. With that high of a serial number I am curious, is it an offset?

Not an offset, wish it was. It is blue but can see orange paint showing in a lot of places. Probably one of our old state highway dept mowing tractors at one time. May
have been put together from pieces because the sheet metal under the steering wheel has the cutout for sos. What confused me was the 660 rather than 661 if it is
actually a 661.

Also, the serial number is 6 digits. The serial number list on here shows all early 2000s with only five digits??

It would appear that a 2000 S.O.S. tractor got a 5 speed transmission from a late model 600 tractor, A 1957 X00 Series tractor STARTED at
SN 116568. 9288 1957 X00 series Fords could have been built after that before the 1958 X01 series started!

(quoted from post at 23:08:03 03/03/21) Also, the serial number is 6 digits. The serial number list on here shows all early 2000s with only five digits??

Click to expand...

The serial numbers listed are the starting serial number for a particular year, so if a lot of them were made in any given year the number of digits in the serial numbers may have had to increase to account for all of the tractors made that year. Since 1964 is the last year listed for serial numbers for the 4 cylinder 2000/4000 series tractors even though they really made them in small batches for years afterward, and the first serial number listed for that year is a 5 digit number, that doesn't mean that later serial numbers didn't reach 6 digits.

Sorry, I missed the part in your original post about the 660 model number being stamped above the serial number. My old age keeps getting older I fear. That definitely means that the transmission is from a 1957 660.But those numbers are stamped into the transmission and only tell you what tractor the transmission was in when it left the factory. The sheet metal or the transmission, or both, and possibly other parts, may have been swapped out over the years. You need to find the assembly date codes for all of the major components to get a consensus of when the majority of the tractor was made and then assume that components with assembly dates several years before or after those of the majority were swapped in at some point.