We have a 2017 Pacifica with 19K miles. For sometime we have noticed a low "thumping" noise while driving the vehicle. It is very annoying and seems to be at all speeds. I have had it back to the dealer 3 times and I had the salesman and one mechanic accompany me on a drive so they could hear the noise. They both confirmed they did. The tires have been rotated (again), front bearings checked, tires balanced (again), and then did a "force test" on the tires and rims (never heard of such test). They said that they found an issue on the force test and re-positioned the tires on the rims. It seemed a little better but now it is back to where it was. This is getting very frustrating. I have owned three previous T&c vans and this one makes the most road noise. I thought they were supposed to be quieter for 2017. Anyone else experienced the problem?
I know this sounds crazy, but you almost certainly need new tires. Or even worse one or more rims is out of round. Hopefully it's the tires becasue they will need replacing someday and cheaper.
I bought a Chrysler in 2001 and once the tires had 16K on them there was a thump thump thump , the dealer could not find the issue. My regular mechanic said I dont care if there are only 1K miles on those tires, they need replacing or one or more of the wheels is out of round. I know that sound and it's an out of round tire/wheel thump sound. He knew within 30 seconds of driving the car. I fought him on it saying impossible there are only 16K miles on the tires.
Sure enough new tires did the trick and the noise never came back.
Form a force test article:
Adding balancing weights can only correct weight differences; it will not compensate for other problems. In fact, in attempting to come up with a balance solution, balancer electronics all start out with the assumption that a tire/wheel assembly is within a certain maximum deviation from round. If an assembly is too far out, the balancer will probably not even be able to make a proper weight correction.
In other words if the tires are too far gone or to far used in a way to make them out of round or imperceptibly worn, inner tensions that can't be seen can do this as well or the rims out of round, no amount of testing and balancing is going to fix the issue. It might make it a bit better, that's it. And becasue your thump and ride are a just a bit better it leads me to believe this is a very possible issue with your tires/wheels.
The only problem is the only way to prove my theory is buy new tires and then new rims if the tires don't take the thump away.