serial number on 100

[haw river cub]

Hey guys, what does a letter J at the end of my 100 farmall serial number mean ?

 

[Graysonsutton]

It may have a Rockford clutch in it

 

[haw river cub]

Ok, whats the difference from a regular clutch ?

 

[Graysonsutton]

A Rockford clutch is the more heavy duty clutch

 

[haw river cub]

Ok, thanks.Thats good to know.

 

[wore out]

For future reference for these older machines, if you go to the official parts site and look at the introductory pages for a given model the codes are usually listed/explained.

https://www.mycnhistore.com/us/en/c...56875BD6/61C96496-EFBE-E111-9FCE-005056875BD6

 

[BarnyardEngineering]

(quoted from post at 11:36:29 09/12/23) A Rockford clutch is the more heavy duty clutch

No. A Rockford clutch is a "regular" clutch. The vast majority of tractors came equipped with a Rockford clutch. In fact by the time of the 100, ALL of the tractors were probably coming with Rockford clutches, but I expect they kept the J to prevent confusion in the service department.

IH was getting clutches from two suppliers, Rockford and Auburn, at least through the letter series. The suffix on the serial number is there for the service department so they knew what clutch disk to have on hand when the tractor came in for service. They typically only replaced the disk, not the pressure plate unless absolutely necessary.

The flywheels are the same, Rockford or Auburn, so if you replace everything it doesn't matter. All the new/rebuilt clutches you can get now are the same style as Rockford.