There is a vibration in truck right around 35 mph that goes away by the time I get up to 40. It's a 2001 Ram 1500, 4WD. Any idea what the cause could be? Trying to save myself a trip to the dealer. It feels like its coming from the center front, right by the cupholders....

Thanks in advance

 

Rotate your tires, see if the vibration moves with them. If it does, get 'em rebalanced.

 

Tires are brand new, less than 300 miles on them. Could it be that they were improperly balanced the first time?

 

Yes. If the tire balancing machine isn't properly calibrated then you could certainly be out of balance. If I remember it right you're supposed to balance the machine once a week, and make sure that it's zero'd out before every tire. Not to mention there is usually a limit of two weights that are put on any given tire.

 

Did the vibration start with the new tires? I've had a set of tires improperly balanced, just go back to the shop they will rebalance them for you if that is the problem

 

Check the tires for an odd ware pattern, could be balance and or alignment.

 

I had the same issue a couple years ago. The rear u-joint was on its way out.

 

Got a rear u-joint heading south, picked up the vibe at about 40-45, now I hear itwhen I slow down, better get it before it gets me!

 

Do a search for Death Wobble. It is caused by the track bar joint/fitting wearing out where it mounts to the frame. I installed a Luc's link to fix it. But check that the tires are balanced and that you haven't broken a belt in tire before you order anything.

 

Also.... if you have aftermarket wheels, and they are lug-centered, make sure they were installed correctly. (although, I think if this were the problem, you would have a major shake, at any speed, that got worse the faster you went.)