Confused - Transmission Codes

[camarosource]

Could someone please shed some light on this confusion..

Seems Chevrolet liked to confuse people with multiple RPO codes for transmissions.

my understanding is that the MX0 is a RPO used to refer that one selected an automatic 4 speed transmissions. However the 2010 Camaro seems to use this as a Generic RPO for the Auto 6?

Upon further documentation (Restoration kits, Books, Magazines, and online sources) there are even more RPO codes for various Transmissions throughout the year referring to the same transmissions..

For example the following shows reference of two RPO codes for the same transmission

Example:

5-speed Manual M49 & MM5
4-speed Auto MD8 & MX0
6-speed Manual M28 & MN6 (Same MN6)
6-speed Manual M29 & MN6 (Same MN6)
MB1 & MM5
M39 & MM5
MK6 & MM5

And many others thought the years..

Going by this it SEEMS to indicate that :

- MM5 was the code to refer that a Manual 5-speed had been selected
- MN6 was the code to refer that an Automatic 6-speed had been selected

But other years become more puzzling.

1. Which of these would show up on your RPO decal? Both M49 and MM5 ?

Referring to the restoration kits make it even worse because of one part they list for example M49 as the transmission for a given engine, and yet other pages mentioning the same indicate MM5 then an RPO list show the transmission as being M49, then another RPO list somewhere else might show it being M49.

2. How exactly can you easily understand what the transmission codes refer to? (Whether they are those above, or others from other years as there are more that I have yet to mention) How do you know which is for the "Denoted selection of a TYPE of tranny (i.e.. a 5-speed manual)" and which refers to the ACTUAL SPECIFIC transmission?

Thanks,

Paul