He said he's had them repacked/inspected every year by a trusted mechanic, so I don't think it's his lack of maintenance in question here... 28 years with the same mechanic is hard to beat... So kinda gotta go with him on that part.. At least I would.. You guys are pretty tough, so who knows? ;)
To the OP, I don't really know... Still on the same set on my 2003 TT, but I only put maybe 3000 miles a year on it. I do the bearings myself every other year. So far so good on the bearings as far as I can tell.. I'm only a shade tree mechanic at best, but have been doing wheel bearings since I was a kid.
My trailer is dual axle, so no idea if a single axle and going on those forest roads can do? My little utility trailer is single axle and over 20 years old and still the same bearings, but of course, it does not have any weight to it and lucky to go over a 100 miles a year!
I'd say just keep doing what you are doing and as long as you don't lose a bearing on the road, it's all good!
Good luck!
Mitch
