[64woodwheel]

I came across this Manifest from a Pontiac plant built 64 GTO w/ tripower and 3.90 gears.

It is coded as metallic brakes 69(2), standard axle preference saf-t-track axle 70(3) , and 3.90 gears 71(P).

So, why is a 3.90 coded as a standard axle preference saf-t-track and a 3.23 coded as a performance axle preference saf-t-track in the second Manifest posted here?

The preference depends on the application such as with or without AC, Trailer, Auto or SM, and engine type. A 3.90 in a GTO was a special order and did not fall under a category of economy, standard or performance preference as far as coding is concerned. I guess Pontiac had to code it as something though, so they picked standard.

According to the axle chart I posted earlier, a 3.23 is considered a performance axle preference for Police and Taxi versions of the Tempest with either a 6 cyl. or 326 2 bbl. with auto trans, and no trailer, and with or without AC. It doesn't really explain why a GTO with a 3.23 would be coded as performance axle preference. Any ideas?