Trailer Vibration

[PFranzese]

I have a question for the experts with trailers and towing.



I have a 16ft Bri-Mar open deck car trailer. Its hooked to the truck below with a round bar weight distribution hitch. At ~60 MPH on the highway I have vibration that seems to be coming from the trailer, it causes the rear of the truck to vibrate up and down. I can see it in the tires on the Jeep on the trailer as well. I shifted the Jeep forward some to increase the tongue weight and it had a very small effect if any on the vibration. I even put balance beads in the trailer tires to eliminate a tire balance issue.



Anybody have any ideas on the cause?

 

[mberry]

Check your rear truck tires for balance, check your shocks to see if one is bad, You may also have a bad tire on the trailer that only shows itself when it has a load on it. The trailer could also need an axle/wheel alignment. Hope this helps. It's all I could think of at the moment.

 

[HBarlow]

Vibration that occurs at highway speed sufficient to shake the rear of the truck can only be caused by a rotational imbalance, most often a bent wheel, bad tire, or unbalanced tire or tires.

Have a good tire shop remove and balance each trailer tire/wheel combination and also the wheel/tires on your truck.

 

[PFranzese]

The truck is new but doesn't mean it isn't the problem. But I should have mentioned that I used to tow the same trailer with a Jeep GC and it did the same thing as well as being underpowered. I have a trip coming up in a few weeks, I'll go over the trailer again to see if I can find anything wrong with the tires or bearings. I try to grease the bearings every other trip at the least, usually two pumps of grease each wheel so I don't have grease shooting everywhere.

 

[HBarlow]

Sorry, I didn't notice that you're driving a brand new truck. It's your trailer wheel/tires.

If you're shooting a couple of strokes of grease in your zerk fitting hubs that frequently you have the greasiest brake drums and brake shoes on the highways.

 

[PFranzese]

Harvey, Thanks for the replys.



Well I guess I have a starting point now.

I'll pull the wheels off and check the drums to make sure the brakes aren't full of grease. While there off I'll check the tires to makes sure they seem ok, not sure what brand they are or how good a tire they are since they are original to the trailer.



How often should I grease the bearings?



I was going with the advice of another person in my Jeep club that greases his every time he takes the trailer out. I would rather know what the guys on this forum do since many have way more experience than I do and some pull them for a living.

 

[Hoefler]

You have a bad tire. Have the tires spun a on a balancing machine and look for one that is out of round.

 

[Bob Cochran]

I have not had this happen but i have heard sometimes rarely a ply will slip during tire manufacturer can cause this. Could be wife's tail but I would guess it would show up when balancing the tire and wheel.

 

[S.Morris]

Very likely you will find a bent rim on trailer or a separated belt in a tire.



Most people don't balance trailer tires... ..... tire shop guys look at you like your nuts when you request it , but well worth the effort in most cases.



Steve

 

[Skydiver]

Some times I thing it is just the nature of the beast. I have a 3 axel trailer the causes my truck to shake violently when unloaded. Once I get on smooth pavement it settles out. 1000 lbs on the front stops the problem as well. I do feel it is resonating. I think it is caused from the out of balance mobile home tires.

 

[HBarlow]

Harvey, Thanks for the replys.

Well I guess I have a starting point now.
I'll pull the wheels off and check the drums to make sure the brakes aren't full of grease. While there off I'll check the tires to makes sure they seem ok, not sure what brand they are or how good a tire they are since they are original to the trailer.

How often should I grease the bearings?

I was going with the advice of another person in my Jeep club that greases his every time he takes the trailer out. I would rather know what the guys on this forum do since many have way more experience than I do and some pull them for a living.

I've never owned a trailer with zerk fittings on the hubs so don't know but would guess greasing once a year would be sufficient.

 

[PFranzese]

Thanks guys, the general concensus seems to be tire or tires are bad in some way. I'll have the tires balanced and checked for out of round and see where that brings me. Hopefully to a smoother place. The real pain is that the truck likes to cruise between 60 and 65 with the 4. 10 gears and thats also where the vibration is, really annoying!