I am sure others have had this same problem and also may have a different / better fix than mine but it only took a few minutes to fix a squeaky (when hitting bumps) dash and stop most all of the windshield weatherstrip movement between the glass and front cap.
This problem started when we were in South Dakota driving thru the Custer State Park on a winding twisty road that I most probably should not have been on in the first place. I believe the twisting was enough to break the bond between the underside of the dash and the front cap. I have inspected this area before but not closely enough to notice the adhesive/glue/sealant, whichever........... had separated. Determined to do something about this issue and with a good flashlight and a younger pair of eyes, (my son helped) we noticed the separation (very small crack).
The fix:
I used my "O"-ring removal tool and scraped away the loose caulk/adhesive/glue..... whatever, the best that I could and all that I could get to without removing parts. Then made a trip to the local hardware store to pickup a tube of 3M-5200 adhesive. Forcing what I could up into the now enlarged crack between the dash and cap, then smoothing it out with a rubber caulking tool. We didn't move the coach for 48 hours hoping it would be enough time to bond adequately.
On our trip to VA. this past week we noticed a remarkable improvement in the dash rattles on I95 in SC, :o , and also a big improvement in windshield to front cap movement. It may not last, but I'm quite happy with my $20.00 fix. ^.^d
For others who are considering using 5200, please read carefully.
"Regular" 5200 is not completely cured for a week.
They DO have a "Fast Cure" 5200 that does cure in 48 hours.
http://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Marine-Adhesive-Sealant-5200-Fast-Cure/?N=5002385+3293241048&rt=rud
Also, 5200 should never be used for anything that you will ever need to remove. 3M 4000/4200 series are for those applications.
For this application, I totally agree with the use of 5200-- fast cure unless you can leave the coach sitting for a week.
Ours also moves but I let it go until it gets a bit of a gap where I can see the outside. Once a year or so, I wait for a hot day and move it back into place. Our driveway and parking has a lot of angles and the coach sounds like it's going to come apart as it twists. I go really slow and hold my breath.
Pierce
I remember the first time that happened to us with our 95 300. I made a u-turn on a two lane blacktop and had to use the bar ditch to make the turn. When I came up out of the grass I looked up at the top left of the windshield and saw an inch gap between the glass and the body. Whoa! That was a big surprise. It's just not a good design but it sure does look good!
jor