How do you differentiate between a 30 cwt and 3- ton

[Phil Waterman]

Hi Keith

"Phil, are you referring to the cab12/13 difference? As far as I know the 6" steering ends with the larger brake drums were introduced with the cab 13. All cab 12s used the 4 7/8" steering ends."

I tried to track down this change over from 5" to 6" steering knuckle when I first got my Pattern 12 and like a lot of things with CMPs the answer is un-clear. Checking the 1944 Parts book it list the brake parts as being listed with the 10:50x16 tires or 10:50x20 tires but when you check the actual knuckle they add a note used after Serial No. 184—28127. So the question now becomes what was the change over date and serial number between Pattern 12 and Pattern 13.