I’ll let them say it in their own words.
http://www.bendbulletin.com/localstate/5213700-151/prineville-railroads-caboose-a-moving-dilemma
Prineville railroad’s caboose a moving dilemma
City of Prineville Railway considers options for moving its old caboose
By Aaron West, The Bulletin
The issue isn’t actually the freight car’s weight, but its height. For a train car, 60,000 pounds is “fairly light,” Wiederholt said, but at 13 feet, 8 inches tall, the caboose’s height would exceed 14 feet — the maximum height allowed on Oregon roads — when it’s loaded onto the back of a truck.
“The height is giving us some challenges,” he said.