Does anyone know what I would need to do to upgrade my trailer from 8" tires to 12"? Is it as simple as just buying the 12" tires and wheels or do I need to change the hubs too?
You might try measuring the bolt holes, and head on down to Walmart. Last time I wandered through their tire section I noticed they had several trailer tires mounted on new rims for the price of just a tire alone! I was thinking of picking up a couple for my trailer and keeping mine for spares.
For the most part yes! You may have to remove any fenders on the trailer but in most cases they will be OK. I did this with a 3 rail bike trailer and it pulls MUCH better at hiway speeds. Walmart, best price. Match lug number, ie 4 or 5 hole wheel.