Does anyone know or remember how they used to balance OLD VW beetle tires - the 4 lug/stud type without a center hole in the rim? I have an old car trailer from the 70's with rims just like that. The brake drums on the trailer are threaded for the wheel studs, and have centering flanges on them Nowadays, if there was an adapter for a rim like that, it's probably long gone to the scrapyard.

Radial trailer tires need to be balanced if driving more than short distances of 5 miles.
The reason for balancing is not so much to make them "ride" better, but to make them "cooler".
Heat is a tires enemy. Unbalanced radial tires generate heat, which makes them fail prematurely.

Don't forget . . . just because you get a 6 or 8 or 10 ply tire, each has it's own MAX SPEED RATING !! . . . most trailer tires, if they have no speed rating on the sidewall, are only rated for 60mph MAX ! . . .

As for the balance issue, you know what it feels like on your car . . . so why would you not want to have the tires on your trailer balanced also ??? An extra little bit of $$$ up front, to allow you to have less worries, and more miles later . . .

Pulling that boat at 70? My rule is if I'm towing my boat jet skis or trailer it is 60 max, or most often less and in the right lane. Too much can happen and I don't want to kill someone else.

I balanced one of my car trailer tires on a new wheel this afternoon, it took less than three ounces using my old bubble balancer. It has a adapter that has Volkswagen and truck adapter written on a decal on the adapter. I've neve had to uses it as I got rid of my V.W. sand rail years ago and I can't mount my 2006 Ram 3500 17 inch truck tires on my manual machine so I take them up to one of the local tire stores and have them do both mounting and balancing

I own 3 trailers. I always have balanced and road force matched on a machine and did myself so I know done right.
I now use balancing beads instead. If you are any RV forums you will see that these have been used for years, not just trailers but big rigs. The beads work well since trailer tires sit idle so much that they can get flat spotted. The beads compensate well.
I have since used beads on my bias tires on my GTS with great success. Just took my ride out for first time this weekend after all winter. Had the usual shimmy for first mile then all smooth after.

Same theory with put the bad tire on the right rear of your car. It is still unbalanced and shaking.

Nope.

We balance 24.5 trailer tires by putting a hammer on the ground beside the sidewall and give them a spin: if it touches the hammer I adjust the runout with the impact until they run dead straight.

Never had a problem.

the reason you would do the above is best on an open diff. just get that tire "rollin" with lots of smoke, and all will be good !