Need some help! When I first start towing my boat, I feel a vibration, can't tell if it is coming from my vehicle or the trailer. It is only for the first couple of miles and then it slowly goes away. It is only when I first start, does not happen anymore unless it sits for a few hours?? Took it out to fill with gas this afternoon and it did it, then brought it to work tonight and did it again. Doesn't do it when I stop at a stop sign and start out again, seems like when it has sat and is "cold". Anybody have any ideas?? Thanks

Doug

If its only when you tow, its most likely coming from the trailer. Check your trailer tires. Have someone drive your truck/trailer and fallow behind it and see if your tires are running true, also they may need balance. Also check to make sure your bearing are tight

I had a vibration a few years back that would only happen under 30mph. here a belt broke on one of my trailer tire as slow speed the tire would wobble, but when the speed increases it would run true. Thought I would live with it till I bought new tires, well on a long trip to Canada the wobbling ended up pulling the bearing apart and had to change a hub in a parking lot, not fun.

You may have a trailer tire that takes a set when it has been sitting for some time.  After you have towed for that couple of miles, the tire will smooth out and run nice and round; make a stop of a few hours and you are right back with the same set and vibration  This happens to a lot of car/truck tires in cold weather.  You get a bad shimmy/vibration until the tire has been run for a distance and kind of warms up.  Just a thought.

Bob

It is only when I tow, but come to think of it, it did it when I towed my utility trailer? Same thing, did it when I first started out then stopped?? Could it be my universal joint going bad? It always clears up after a few miles, that is what I don't understand. I just had the bearring replaced on my boat trailer and my other trailer is brand new, but I will check out the tires. How would I know if they need balanced? On my other truck, I never felt anything. Thanks, Doug

well you take your trailer to a auto shop and have them check the tires.

Does your trailer have surge brakes?  Perhaps they're sticking.  When they heat up a little, it frees them up?  

Along those lines, if you do have surge brakes, carefully check around the hitch area to see if anything is lodged in there that would prevent the brakes from working properly.  Sometimes marine shops will jerry-rig it to make it easier to push around the lot.  And since you just took it in to have work done on it....  

Plus, if the lot was a dirt area with rocks in it, or you launched at a dirt ramp recently, you may have a rock lodged in between the calipers (happened to me once).  Just a thought.

Some tires will get a flat spot from sitting under inflated that will go away with heat.

Garnet

No surge brakes. A friend suggested after I come back from fishing to block the tires off the ground until the next week when I go fishing to see if it is flat spots on the tire. Said if it is flat spots they shouldn't develop being jacked up?? Going to try this, but is this bad, the flat spots, or is it just something that happens? Would new tires stop this? Thanks for ALL the help.

Doug