Why are the numbers 1-6 on info display? They can
be adjusted by the +/- button on my gear shift but
I'm not sure exactly what it does or when I should
or shouldn't use it
They show what gear the transmission is operating in. Refer to the owner's manual for more information.
Bob's right, when your in that mode, usually towing, while driving you can shift gears manually if you want, you really should read the owners manual, it will tell you how too operate this system properly, and there are do's and don'ts on this system.
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