1960 vintage John Deere 830 tractor pull wheels up wheelie

Our original 1960 John Deere 830 yanking on the sled with the throttle set to idle. Listen to the pistons hammering away. It came equipped from the factory with a 472 cubic inch (7.7 liter) 16 to 1 compression 2 cylinder diesel engine. The tractor weighs 12,000+ pounds and the sled it's pulling weighs over 30,000 pounds.