Took the strut out again tonight and tightened the top nut again. Fixed again for now! Perhaps it has something to do with the strut brand, it's an "Evolution Strut Assembly". Has anyone ever heard of this type before. I know Monroes, KYB and Gabriel are more common, maybe I should have used one of those, but i couldn't get one on that particular day and I needed it then.

 

So I took the left front strut out tonight. I marked the nut and shaft with a sharpie so I could tell if the nut turned when I tried to tighten it. I first put my spring compressor on and compressed the spring a bit just to relieve some pressure from the top bearing. I also pried around down on the nut to see if I could tell if it was loose. It was not. I put my 1/2" electric impact on it and tightened. The nut barely turned. Not even 1/8 of a turn. Just barely off the mark I put with the sharpie. All the other suspension components seemed tight.
Now the good news. When I put it all back together and test drove it, it was better. I went up and down the curb over and over and drove down a bumpy road. A couple times going up the curb it sounded like it tried to clunk, but it was definitely improved. Time will tell. I really don't expect this to last but maybe I'll get lucky. I can't imagine that nut barely turning just a little bit could have been the problem. Thanks again for all replies.

 

Hopefully it is resolved.

 

I could not leave well enough alone and took the strut back out, compressed the spring and removed the top bearing cap. (This is a Monroe quick strut). First thing I noticed was the upper bearing, or should I say lack of one. The upper bearing is actually a flat ring made of plastic and a teflon type material that goes around the top cap. The strut rod goes through the top cap and secured with the nut. The top cap is pretty thin material, maybe 1/8" thick.
I cleaned the threads with a degreaser, put it all back together using loctite on the strut nut and threads and tightened it very tight. It is hard to tighten without the whole rod turning, so I had to vice grip it way up high under the boot and bumper. There is no way for the vice grip marks on the rod to get into the seal due to the bumper.
Still sounds good after the test drive. I hope it is fixed. Makes me think I should now do the same to the right side.

 

Good post, thanks for detail!

I have seen more than one post about upper bolt on aftermarket GC struts coming loose. This is surely not the fault of Dodge designers because the problem does not plague OEM units.. I have never disassembled my front strut assy so I can't comment on the inability to hold the rod from turning while tightening the top nut. Most rods have an allen hole, hex bolt head or flat end on the strut rod allowing you to hold it with a tool to torque the nut to spec. If the end is blunt or covered by something I suppose the strut mfrs are using a special jig to hold the rod without damaging the finish.

My original struts have 225K mi and still function like new with no leakage. I'm an HPDE performance driving instructor and I can tell you my struts have excellent dampening characteristics. They are rusted but don't clunk at all so the rod nuts remain tight from factory assembly 13 years ago.

 

I'm thinking that I may be headed in the direction of the strut nut being loose. A little less than two years ago, I totally rebuilt the front suspension meaning everything that moved and probably a few things that didn't. However, now I have the clunk back.
I replaced the sway bar bushings and that didn't help a bit. Next up are the sway bar links but I don't have a warm and fuzzy because I used pretty much top end units before and I wouldn't think that 30,000 miles would result in the links going bad but we'll see.

 

Got by clunk free for 3 weeks, clunking again. I spoke with the place that sold me the strut and they agreed to replace it under warranty. Guess I'll try my chances with a new one. Hopefully get it swapped out later this week.

 

If you discover the nut is loose again you may be missing some spacers or washers of some sort which could prevent the nut from torquing tight to preload against the flange. It may be bottoming out on thread bottom or something wrong. I would also try using a air powered torque wrench on it and possibly drill thru the nut and rod to install a cotter pin. An air powered torque wrench relies upon rapid hammer-like movements which allow a nut or bolt to torque tight without firmly holding the other end. It relies upon angular momentum to prevent the center rod from twisting with the nut. You can't get that effect from hand tools.

 

Exhanged my clunky strut for a new one under warranty(3 months in on 1 year warranty). The place that sold me the strut said it wasn't the first time they've had a strut come back for this reason. Installed the new strut and clunk free again. Let's hope it's fixed for good this time.

 

I too finally talked to the store (Advance auto parts) that sold me the struts and explained the noise/clunking. He said no problem bring it back and I'll give you another. I changed it out and so far so good. Everything feels solid and tight and no clunking.

I did end up with a slightly crooked steering wheel from changing all the front end parts. I took it in for an alignment ($90) and the wheel was still crooked, about 3/4 inch turned to the right. Rather than hassle with returning it for a do over I ended up adjusting the tie rods myself about a 1/4 turn each, pointing the front wheels just a tad to the right. The steering wheel is now straight and the van drives fine. Oh the joy of owning a 7 year old Grand Caravan.