Randy Chrisman built his son a scaled, working replica of a full-sized Cat D5.

The D.5 runs on a 24-horsepower Cat 1.1-liter diesel engine obtained from the local Holt Cat dealership 

The mini dozer has Parker hydraulics. The straight blade is about 50 inches wide, 18 inches tall and 240 pounds.

He first intended to convert a stand-on mini track loader into a mini dozer, but the price for even a used, beat-up model was way too high. He had already begun crunching numbers and learned that the small Cat engine wasn’t out of budget. So he decided to build it himself with some help from friends.

https://www.equipmentworld.com/construction-equipment/article/15678759/dad-builds-elaborate-mini-cat-d5-dozer-replica-video