I've been running a modified snowmobile trailer (Sledbed) I've had for about 14 years. I've replaced the axle on the trailer after making the mistake of having the spindle rewelded. I put about 10K miles on each set of tires and run it on the highway at 75 - 85 mph. If you've got the little wheels, lube the bearings about every 500 - 750 miles, use marine grease because I like to back into the water to load up where boatramps allow. I like having the torsion suspension thats rated at ~2400 lbs because when I've got a heavy load on bumpy roads, that 1000 lb load probably doubles when hitting a big swale-type bump at 65 mph on the freeway or that bump that gets your trailer airborne on the rough road to the put-in.
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