RickD is close on the Fuel Tanks. After dropping and to 3/4 full on the front and switching to the rear tank, the computer will switch back to the front tank when the rear tank reaches 1/4 full.
When you set the Engine Brake to "ON" taking your foot off the accelerator will engage the engine braking feature. If you press the brake pedal, it will then force the transmission to downshift.
When you set the Engine Brake to "AUTO" it will remember your speed when you take your foot off the accelerator and the system will engage and work to maintain that speed when going down a hill and it senses the vehicle is trying to accelerate on its own.
AUTO is less aggressive than ON but you should not use the system on slick roads.
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