Ok, got a question for you guys. I have a stock '06 2500 (see signature) and a 20' Flatbed 14K lbs trailer. When I tow it with the Dodge, it has a nice vibration in the truck from about 55mph to 60mph. The truck does not vibrate at all when unloaded. The tires on the trailer look real good, have good tread and are 16" E load rated. I even got them balanced thinking that might be the problem. None of them look like they have cord seperation. I even took the front two tires off the trailer (its a tandem single wheel) and that did not help. I have 50psi in the trailer tires. I never noticed any vibration from the trailer towing it behind my Ford, but that had a little softer rear suspension. It vibrates un-loaded and loaded with about 3000lbs.

I am going to go to a friend of mines and hook up to his trailer to see if it does it with his trailer, indicating it would be the truck. I might eveen try and tow the trailer behind the Explorer to see if that vibrates while pulling it.

Any ideas? All the suspension looks good, and the trailer really hasn't been used much since new. This is the only load I have had on the truck since I have gotten it.

Thanks for any help,

Tobin

 

may want to check u-joints. with the load on the truck it can change the angle of the driveshaft causing a vibration

 

Ill take a look at the U-joints today. Any other ideas?

Thanks,
Tobin

 

Does the truck sag in the rear? Maybe air bags to help level the truck, getting the driveline (u-joints) back into it's normal operating angle.

Tony

 

It squats some, but I am talking about the trailer unloaded and with a very light load (~3000lbs). The trailer sits pretty level and the truck barely squats in the rear when I put the trailer on it.

Thanks,
Tobin

 

Has the truck sat for long periods? i.e. could there be flat spots on the tires that show up with that load / speed?

 

I think the tires are rated for 65-70psi. Maybe try that?

 

All 8 u-joints look good. I can try pumping the tires up some, but I just don't see how that would help as they aren't bulging or squating at all.

Thanks,
Tobin

 

I don't think it sat much, but I just got it about 2 months ago.

Tobin

 

Jacked up all tires on truck and trailer to 70 psi, still does it. Towed a friend trailer that is about comperable but 24' long, and no vibration. Friend of mine is going to tow my trailer with his truck and see how it does. Very annoying, I really don't want to have to get rid of the trailer if it just does it with my truck.

Tobin

 

Look at the Dodge TSBs . It seems I remember seeing one about this issue and the fix was shimming the carrier bearing down to improve loaded driveline angle.

 

Bent rim or bad tire? Putting more weight on the bent part amplifies the vibration, because loaded suspension is less responsive, and wont absorb the vib.

 

Could be axle alignment on the trailer. Check the tires for feathering.

 

I'd say try towing the trailer with a different truck.

You may have a bent wheel, alignment issue, broken belt on a tire that isn't easy to see, or some other issue with the trailer.

Also, it hasn't been mentioned yet, but inspect your hitch closely, and check the related bolts and hardware.

 

Thanks for the ideas, I will give them all a look. I am going to tow the trailer with a buddies truck to see if still has the shake.

I would say it shakes the truck more than a vibration.

I gotta tow a buddies boat, I will see how it does with that, it is a decent size boat.

Thanks,
Tobin