300 massey crawler
Need to supply a lot more info. Is there a driveshaft from transmission to the bevel gear?
Put a fresh cat-perkins torbo diesel .when I get a small load of dirt that tracks stop.. It's worse I reverse. Change filters and oil. It turns and stops Tracks slow in any range
Transmission or torque converter could need work or the trans. pump. I'm curious why you would put a fresh engine in a 50+ year old dozer without knowing if the rest of the machine was any good, especially a dozer with next to no parts support? If the new engine with a turbo is a bunch more HP could be hard on the drivetrain if you get it working properly. Should be able to find a service manual from the Agco site or online.