2005 Montana SV6 need some advice

[Tripletmomplus2]

We purchased a 2005 Montana SV6 last week, this van was owned by a 84 yo man and his 87 yo wife for the since it had a little over 4000 miles on it, and it now has 95,400. It looks brand new, has been kept in garage when not driven.
they traded it in for a smaller vehicle and the wife does not drive. Was able to make contact with previous owner through tire purchase records left in glove box. So made contact and went for a visit to pick up some more paperwork they had to give me for all the service work they have had done through the years and also the extra set of keys and key fob...

This van runs great, after purchase we spent another 1000.00 to get some things fixed. Replaced the pasenger side mirror, new rear shocks, 2 new tires, front wheel hub assembley.....

Ok so far so good, BUT we have a very strange issue that my mechanic of 20 plus years cannot seem to find the reason why....

I will try to describe it as best as I can....going over a normal size speed bump, no issue, very smooth ride, no noise, going over normal little bumps in the road, no issue, normal but when you drop the drivers side tire in say a man hole cover, the sits about 2-3 inches below the road grade, OMG there is a terrible clunking noise that can be felt under the drivers seat and right behind it, I know because I made my sister sit right behind me while testing the noise to see where it was coming from.

I also had my mechanic ride along to confirm the horrible noise, while the van was on the lift, 3 adults including myself, pushed, pulled, inspected the under side of this van and cannot find anything wrong, in fact it looks very good for the age of the van. But for the life of me we cannot find anything wrong...

While visting with the previous owner, he said it started about a year ago and he had several mechanics also check it out and they could not find anything either....

Any clues or ideas as to what this might be??

thanks
Donna/Indiana

 

[melsg5]

checked for a broken motor/transmission mount? checked that the exhaust system isnt hitting anything?

 

[Steelcity]

Welcome to the forum and congrats on the purchase on the van. We had a 2000 back a few years ago and we had a similar problem and it was a half broken sway bar that was flexing on bumps and making a terrible noise ,so replaced that and the bushings and pins and noise went away . Not sure if your van is the same generation as the 2000 but this will give you something to go on . Also you could try lubing up the control arms/bushings. Good luck and keep us posted/educated.

 

[JoseC]

I have a Chevy Venture that makes the same noise. No clue yet...