K2500 6.0 gas 139,000 miles, 4.10 gear ratio, excellent tow rig. Never been on dirt roads, tight no rattles, new GM front wheel bearing hubs, 10 ply wrangler tires, everything has been serviced and nothing needs fixing. Would make a great farm pu or tow rig. Transmission fluid was bright red when I changed filter. I pulled a tandem trailer to Ellsworth and picked up a car. Transmission fluid ran between 140-160 degrees