I am about to install a windshield in my car. I got new glass from Sierra Madre Collection and am using the 914 Rubber black gasket that replaces the chrome trim. I planned to use the Butyl stuff but the guy who dropped off the glass said it's better to use Dow's U-428 Plus Auto Glass Window Adhesive (in a caulk tube). It's a Urethane Primer Less Adhesive Glue Sealant.

Does it really matter? I thought I heard somewhere that being that these 914's flex a bit, it's best to use the Butyl sealant as the urethane can get to hard.

Anyone with a better understanding on this? thanks

I opted for 5/16th butyl tape because the urethane sets hard. . If there is any flex in the windshield frame or cowl you risk a crack forming the butyl allows for a little bit of flex

that's what I was thinking too - thanks

Mine was installed using 1/4" by an installer that did not know what he was doing....it needed to be bigger, I'll fixed it myself soon....Do not cut the rubber short at the seam...mine shrunk after 6 months of just sitting in the garage. He also did not center the windshield, so the rubber did not lay well on one side. Be ready for the corners to roll up...I strapped a bean bag over the corners after a drop of adhesive under the rubber to help hold it down...left it for a week, and it stayed...Actually got pissed off at the split in the rubber and pulled it all off...I personally think the rubber vertical piece needs to have a bit thicker profile...but it may have been user error...

I had mine installed using the Urethane, NOT the butyl. If you bought the butyl from me drop it back for a credit if you wish. It's much easier to manipulate the Urethane with the slightly larger seal attached. The real key is to get it centered and use some painters tape to hold for at least 3 hours.