My trailer has been 'popping' when making turns. Reading this forum, I've realized that I need to replace the spring bushing.
Here is an intermediate update on the process of replacing spring bushings on a tandem axle trailer for a 2003 520VX. Keep in mind that I've never done this particular repair before.
Ordered parts from Ranger Parts using my trailer serial number. As we've already read, they recommended replacing all the hardware - bolts, nuts & equalizer hanger straps.
Parts neeeded for tandem trailer:
14 qty of part #9633090, spring bushings, 11/16OD X 9/16ID X 1 3/4" long ($1.56ea)
14 qty of part #9600581, nylock nut, 9/16", zinc ($0.43ea)
14 qty of part #9600580, shackle bolt, 9/16" X 3.12", zinc ($1.62ea)
8 qty of part #9615044, Equalizer hanger strap 4", galvanized ($2.09ea)
The bolts have a 1" section that is threaded. The rest is a smooth shoulder except for the last 1/4" by the bolt head which is knurled. Playing with all the parts, I found that the equalizer hangers did not slide up to the knurl section. Past experience doing auto repair leads me to believe the hangers should slide freely up until the knurled section. Called up Ranger Parts & spoke to Ted in Parts. He confirmed that I have the correct parts. Ted referred me to Chris in trailer repair. Chris confirmed that the hangers actually should slide onto the bolt freely up to the knurled section. A little work with a rat tail file to remove some (excess??) galvanizing took care of the issue. Per Chris, they install the bolts with an impact gun until the knurled section is pulled into the hanger and the bolt head bottoms out. Nuts should then be backed off "one full turn".
I'm hoping to do the job Friday or early next week. I'll have the boat/trailer completely supported on jackstands & will support/adjust the axles with floor jacks as needed. I don't anticipate any issues with the install. I'll update the thread if there are any issues or tricks that might not be obvious.
Hope this is helpful for anybody considering doing the job.