GM Chevrolet Avalanche - Manual (Page 317)

Dinghy Towing Two-Wheel-Drive Vehicles
Notice: If you tow your vehicle with all four wheels
on the ground, the drivetrain components could
be damaged. The repairs would not be covered by
your warranty. Do not tow your vehicle with all
four wheels on the ground.
Two-wheel drive vehicles should not be towed with
all four wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
Four-Wheel Drive Vehicles Only
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