I bought a new flat bed trailer today, a 5 1/2 x 10 with ramp and wood floors. Drove up to Janesville to pick up a mower deck. On the way up when I got over 60 the truck shook like crazy. Turned out the wheels were not properly tightened, and on the way back with weight, the shaking was about half, right around 65 was the worst. I can't believe how bad the truck was shaking from an improperly tightened trailer wheel. I didn't see any shaking of the trailer though. Other than that the truck did handle well, no odd steering like in the past when having a trailer connected. Going to pull the wheels off ad reindex them and tighten them properly and hope that the truck no longer shakes.

 

That's why they make torque wenches.

But you may also need to have the trailer tires balanced. The tires and wheels on a cheap trailer are probably nowhere near in balance

 

Definitely get the tires balanced. I have a similar trailer (7x11) and whether empty or loaded, I basically can't tell it's back there.

 

Yes, and its not just the F150, we had an empty boat trailer shake the crap out of a dodge 2500 last year. Story goes like this. A trailer brake caliper locked up so hard that it sheared the bolt that was holding it to the hub. The result was that the caliper fell off and was bouncing around in the bottom of the wheel. This of course happened when I was at the lake with a ton of friends and family ready for a day on the water.

In a rush I decided to put the boat in the water and tow the trailer to a local mechanic and let him deal /w it. I didnt stop to take the wheel off and get the caliper out of the wheel. Total trip to the mechanic was under 10 miles on country roads so I didnt think it would be a big deal. Turns out anything above 40mph resulted in the trailer bouncing and shaking the crap out of the truck. Like shaking enough to be scary, and this was in a heavy 2500 diesel truck. The caliper couldnt have been more than 3lbs but it upset the wheel balance enough to really make travel dangerous. Lesson learned.

If that was enough to shake a heavy 3/4 ton I dont know what it would have done to my light F150.

 

I am having this issue with my 6x10 dump trailer. Previous vehicle had no issues at all, this truck shakes like crazy around 55-60. Not sure what to do as nothing has changed with the trailer.