While we are on the topic of manuals and documentation,
FCC keeps a lot of up-to-date manuals at
there is the newest version of the "Know Your Chassis" slide deck.
On page 23 it provides the first explanation that I have found of how to use the "Mode" button on my Allison transmission. When I press the mode button the light comes on, but it does not tell me what the mode is. According to page 23, the Mode On is for the best fuel economy and the Mode Off is best performance, such as in mountains. I had always thought that it was the other way around and normally drive with the mode off. The difference between the two is very subtle, so it was hard for me to tell.
I agree that these manuals are not full service manuals, but I'm not a licensed mechanic and wouldn't want to do the things that need such a manual. Compared to the service documentation provided by car manufacturers, however, this is quite impressive. I have bought Ford and GM service manuals and they were 2 or 3 volumes, but I never needed that much detail for the things that I would do. The FCC manuals that are readily available are somewhere in between the detail a car owners manual and a full service manual.
In addition, you can register your VIN and get vehiclespecific information at