What size truck is it from?

I looked at the rear axle from a 1951 1/2 ton truck and I could not find any markings on it. It still had the drum on it so there are a few parts I could not see but I didn't see anything on the shaft. Looking at the parts book (links below) they say stamped #XXXXXX on both the 1947-50 and 1951-57 axles so maybe it is on there somewhere but I couldn't find it.

http://chevy.oldcarmanualproject.com/1929_57chevyparts/57cmpc0467.htm

http://chevy.oldcarmanualproject.com/1929_57chevyparts/57cmpc0473.htm

Last edited by 1866yellowboy; 10/14/2015 12:44 AM.