The only HOn3 trucks I have used are the Kadee #716's. They require assembly, and I highly recommend using their "Truck Assembly Fixture," if you don't already have it. They can be a bear to assemble without the fixture/jig. [:-banghead]
The trucks on this scratchbuilt HOn3 tool caboose are the Kadees.
Now, if you'll excuse me, I'm a busy man. I have a railroad to run.