Re: How fast do you tow?
I usually stay a bit under the speed limit, whatever that happens to be where I am at the time. My max limit, no matter where I am, is 60 mph.
Special circumstances such as rain or heavy traffic, will cause me to back off even more. My van is rated to tow up to 6,300 pounds, but my boat/trailer only weighs about 2,000, so I have a pretty big safety margin in general. Even so, that rating assumes trailer brakes and anti-sway devices, so caution seems to be the better way to go.
My biggest concern is braking and my van does very well with that. I've had to do panic stops with the boat behind me, and have had no problems, mostly because I am constantly adjusting interval, as people cut in front of me. In heavy traffic, that is hard to do, but just slowing down will usually keep me within a "zone" that enables me to stop easily. The anti-lock braking system also helps quite a bit with controllability.
Next on the list is tire and/or bearing failures. I've had both occur and the trailer has remained very controllable on each occasion. I had a massive and premature bearing failure on one axle end last Saturday night, while traveling at 60 mph and the trailer did fine. The tire was wobbling all over the place, but it didn't come off and I was able to let off the gas, slow down and get to the shoulder.
Some moron (me

), forgot to put the outer washer on. before the nut, while replacing the bearings about 6 months ago! I have the axle nuts that don't have the "castle" portion - there is a castle cap that goes over them and the cotter key goes through that. Unfortunately, if you don't put the washer in, the nut tightens down onto the axle too much and the cap fits too far away from the cotter key hole in the axle, to properly prevent the nut from moving. Sooooooooooooo ...... mine did move and the hub moved outward just a little bit, which was enough for the tire to wobble imperceptibly and destroy the bearings, over time.
Note to self: When you see a little bit of grease on the inside of one of the trailer wheel hubs and the seal is pretty new,
ask yourself why!!!!! It just might be the tip that the hub has moved outward, just enough to let the seal get sloppy and sling grease!
???