Knocking sound underneath front of van

I have a 1998 Dodge Caravan. When I am driving over smooth road or roads with dips I don't hear any noise till I get to the bumpy roads then it sounds like something is very loose in the front end around the front tire area's. It's almost like a knocking sound on the floor boards. Someone had mentioned Struts. I am not familiar with Struts at all, could this be the problem or are these vans known for something else. The steering seems very tight and everything seems fine till I hit the bumps. Now if it is the struts, are these able to be done yourself or are they just a dealer event.
Thanks for any help, It's greatly appreciated.
Moon....

You don't say how many miles you have on the van but this sounds like a worn out strut. They will make a knocking sound when they begin to wear out. If you remove the front tires and check to make sure the sway bar is not broken or loose that will eliminate one source. If it proves to be ok then the struts will need replaced.

You do not need to go to a dealer to have them changed most shops who do suspension like Firestone, Midas, Sears, Pep Boys, Monroe and etc can all do struts for you. You can do the job yourself but you must have a strut compresser designed specifically for struts. Anything else is dangerous. If you are not familiar with the job have someone else do it for you. You will also need an alignment after the struts are changed.

You don't say how many miles you have on the van but this sounds like a worn out strut. They will make a knocking sound when they begin to wear out. If you remove the front tires and check to make sure the sway bar is not broken or loose that will eliminate one source. If it proves to be ok then the struts will need replaced.

You do not need to go to a dealer to have them changed most shops who do suspension like Firestone, Midas, Sears, Pep Boys, Monroe and etc can all do struts for you. You can do the job yourself but you must have a strut compresser designed specifically for struts. Anything else is dangerous. If you are not familiar with the job have someone else do it for you. You will also need an alignment after the struts are changed.


The van has 156,000 miles

The van has 156,000 miles
Possibly sway bar bushings.

it's the sway bar bushings, i see this every day, sometimes multiple times a day. on smooth street it sounds fine, then when you hit a pothole or a dip, you'll hear a clunking sound coming from under the car. the bushings are easy to replace, 1 bolt/hut holds a bracket, once the bracket is off, the bushing slides off the sway bar, and you can slip on another one. $60 bushings, 15 min repair.

that was supposed to say "1 bolt/nut"

I had the same problem....was driving me nuts. The bushings did the trick. Get the part from the dealer, about $10, and bring in your VIN. The first dealer I called told me my 2001 T&C needed the 26.5 mm bushings. They were closed when I went to pick up so I went to another dealer...they told me I needed the 26mm. I gave them my VIN and they were right. It's not a hard fix. It took me about an hour start to finish.