I am new to this, but I have a 2002 Dodge Ram 3500 Dually, pulling a 50ft
wedge 3 car trailer, and at 40-50mph the back of the pickup shakes from side to side really bad. Over 50mph or under 40 mph the pickup drives fine and only when pulling the trailer does this happen. It is a brand new trailer. Any help appreciated.

 

Sounds like you're a bit light on tongue-load...

 

I will try loading it and see, but I would think that, that would cause it to happen at any speed? I will try loading it though. Thanks

 

I loaded the trailer and it still does the shake from side to side at 40-50 mph.
any advise.

 

Have you checked to see if everything is OK on the new trailer? Tires out of balance, for instance - since the truck won't shake by itself.

 

Try posting this on the towing and hauling/RV page. Kurt

 

The trailer is brand new and just got certified. no problems with the trailer