This parts group covers the front springs used on the AA-chassis from production start in 1927 through 12/32. There were three production front spring and one service-only front springs.

The AA-5310-A/B spring assemblies were used on AA131 trucks through December 1929. The AA-5310-C/D spring assemblies were used on AA112, AA131 and AA157 trucks starting with all frames released January 1930 through production end in December 1932.

The four front spring assemblies were as follows:

• AA-5310 – A 12-leaf spring assembly with 1-3/4″ wide leaves. Used from the beginning of production through 1929. This was AA-5310 (without suffix until August 1929).
• AA-5310-B – An 18-leaf spring assembly with 1-3/4″ wide leaves. A service-only spring assembly released in August 1929 as a replacement for the AA-5310-A 12-leaf spring.
• AA-5310-C – A 13-leaf spring assembly with 2-1/4″ wide leaves. Used January 1930 to the end of production for the AA112 and AA131.
• AA-5310-D – A 14-leaf spring assembly with 2-1/4″ wide leaves. Used on AA157 trucks. Beginning in August 1930, this spring assembly could be ordered as special equipment from the factory for the AA131.