I have an older triple axle trailer. When towing, it dog tracks slightly. I can also see in my mirror that the axles are out of line ever so slightly. What is the procedure to align them? Thanks

I don't know if there is a "proper" way to do it. But, I did it a couple years ago with a laser level and a tape measure.

I had the boat off, and the trailer suspended on jack stands. I placed the level against the front of the brake rotors, and used the tape measure to to adjust the axles for equal measurements from the I-beam at all four corners.

It worked great, and about a year after I did so, the boat and trailer made a successful trip from VA to MT with no issues. Good luck.

Measure from the tip of the ball receiver to the tips of the axle stups and square. Then set subsequent axles paralel to the first one.