Interior component quieting

[Last Indian]

For those folks who care, this is about how you might chose to quiet certain interior parts that tend to make noise because of improper material match as well as the way in which the OEMs started to build components. This is of a particular problem for the later generations of Pontiacs & cars in general, from about 1990 to 2009 for Pontiac.

As these cars age and their materials age, they take compression set, dry out and become contaminated with all sorts of products and this problem only exacerbates with age! The fact is if you have a quiet riding car and your door panels, console, dash etc. make noise it’s annoying. There are also ways in which to make an already quiet vehicle even quieter! I will attempt to detail both. 

One problem with newer style components introduced by the OEMs from the late 80s to about 09 - 12, was basically the ability to make adjustments to components coupled with the fact that they didn’t isolate panels as they once did or there is no buffing of components, and if they have adjustments more often than not it requires bending something. Not unclamping moving and re-clamping to adjust a part. This along with the plastic fastener and no real outer perimeter clamping gives you panel movement, albeit minuscule, any can and does create that subtle noise that just irritates! I would explain how this was all handled so eloquently back in the day, but this isn’t the point of this subject. So I will start with the door panels and if this seems of interest to folks, I will move to other components that suffer from similar issues. 

Old skool OEM door panels were done in such a way that the interior panel was both isolated and locked into position. The isolation was done by using a waterproof treated paper that actually had a slippery surface on the panel side that interfaced the interior door panel. Plus the attaching inserts bayoneted into a plastic plug that actually stood the panel out slightly. The paper allowed minuscule movement while keeping things quiet as did the plastic inserts that were housed in the door frame. Additionally the top of the door panels actually clipped into brackets that served to secure the top of the panel as well as limit the movement of the glass when down. While at the arm rest and the bottom of the door were screws that clamped the door panel tight. The new style panels, late “80s” to about “12” have none of these. They take a formed plastic panel and at best wrap it in a fabric of some kind and fit it to painted steel that gives a coefficient of friction around .60 which is high enough to be sticky, but not sticky enough to stop movement, which can create a squeak type noise! They use nylon fasteners that don’t necessarily hold the panel tight enough to stop all movement and usually one or two screws at the pull handle only to secure the pull handle to the door for closing purposes. 

So the following is what I’ve done to place an Old Skool environment back into the new style design without changing the original look that the designer wanted. Isolation as well as a lock type environment needed to be returned as well as some needed sound deadening!

The first thing like most projects is to gather materials! I wanted the thickest visqueen I could find! For me that was at a local fabric store, 32 mils, the heaviest felt, 100 mils, that I could find to use as a sound barrier. A lighter weight felt, 40 mils, for uses as a movement buffer and better fitting plastic panel push fasteners. Contact cement, Great Stuff expandable urethane foam, liquid nails Fuze*It and last, but not least, 3Ms multi use duct tape (black).

My suggestion, to avoid breaking any of the push fastener stanchions, not the fastener itself, that are an integral part of the door panel itself, is to use a 1” putty knife that’s sharpened to shear the fasteners as opposed to just pulling on the panel. As most folks don’t have the proper tool to get under the panel and fastener itself, if you do, than use that. Remove any screws, than all wiring that is attach to the panel and than remove the panel carefully! Now you are ready to start cleanup. Cleanup what you determine is needed, that’s up to you, but remember dirt and grime are sheet metals enemy.

My detailing will be of “97” – “03” Grand Prix so you will need to interpolate this to your vehicle.
Now you can start to work on the door panels and making the pieces for the door interface to the door panel, visqueen and heavy felt, that will attach to the door. The door front panels have a heavy cotton pad/sheet adhered to it, remove this and set aside, you will reuse it. In the front panel at the bottom back part of the panel, where the red reflector/ light is, there is a very large hollow area. Your may choose to do what I did and fill this area with Great Stuff, see associated picture. You’ll need to build a wall around the reflector/ light to keep it isolated from the foam. Once you have applied the Great Stuff and it has cured, take a razor knife and cut away what is unneeded. This addition makes a marked difference in noise once all panels are finished with the additional work that needs done and reinstalled.

If you have a 4 door, similar work is done to the rear panel with great stuff, but this is done more to adhere the existing styrofoam insert to the door panel itself. The purpose of this is that the styrofoam insert again moves within the door panel creating its own noise when it’s supposed to quiet things. Using great stuff adheres the styrofoam without attacking it and also fills gaps and adds additional noise reduction. Also in the back panel there is a second styrofoam insert above the lower one, this one is retained by a plastic plate that is held by 4 retaining nuts. In the same manner in which the lower one can make noise so does this one. This foam piece though I use a different adhesive. I use liquid nails Fuze*It, this makes a strong bond without attacking the styrofoam and with this insert we don’t need too fill gaps and we don’t want to cause the insert to be push outward, as great stuff tends to do.

You should now have laid out and cut your visqueen and felt coverings for the doors from the OEM pieces. So since the doors are cleaned how you want them and the coverings are finished, it’s time to install them! This is where you’ll use the 3M multi use duct tape. Why this tape? Well when you use it you’ll understand, but the adhesion is next to none, which for this application is what you want. One reminder, don’t forget to make holes in both coverings for the screw holes for attaching the center of the panel. My advice is start at the top of the door with a few short pieces of tape, 3-4 inches long, on each end and in the middle. Making sure to align all the clearance holes for the plastic fasteners and screws properly. As you work through each covering, visqueen than felt do the entire perimeter in the 3M tape. Now with both coverings installed make sure all needed holes for screws and panel insert fasteners are clear as well as electrical pigtails have been brought through.

Now we turn to the door panel and adding the thinner felt to the door panels. Newer panels fit directly against the painted door frame, unlike old style panel as explained previously, and they are held taunt via the plastic fasteners. The long term problem with this is as the panels lose elasticity, take a compression set and get a bit more tacky, due to overall contamination and age, they start to squeak as they oscillate on the painted door frame. I take a lightweight black felt about a yard and a half long and cut strips about 3/4- to 1” wide. This is so I can run a felt edge around the perimeter of the door panel. Once I have cut my strips, I take the contact cement and an acid brush and paint a bead of cement on the back border edge of the panel about as wide as the strips. After 10 minutes I paint a second coat and than I paint a single coat of cement on one side of the felt. After about 5 minutes I start to lay the felt in place, making sure the the felt sits just slightly outside the edge of the panel, once installed you will not see the edge of felt if done right, but you’re trying the ensure that the felt is the buffer between the panel and the door frame!

Now to install the fasteners. In the case of the 2000 GP I used Balkamp fasteners, part# 665-1632 & 665-3465. These fit just a little tighter than the OEM part, which makes for a tighter hold to the door frame. The 665-1632 I use for the interior mounting stanchions that can’t be reached with a tool so they have to be pulled, aka the panel has to be pulled on, but for the perimeter I use the 665-3465 as they hold tighter. 

Well it’s time to install the panels! So make sure everything is as it needs to be because the last thing you want is to have to take the panel right back off. Check that all electrical is pulled through both coverings and where you want it. That all holes that needed cut have been done, that everything is taped. Make sure if you removed the inside window glass weather molding that bayonets to the steel edge is in place.

below is a front panel showing the ear that houses the tweeter. This is a separate added piece that is just affixed by melting two plastic pins. In turn this piece move and can make noise. By glueing it with th fuze it product it becomes much more rigid.

This is the door frame with the heavy visqueen installed

Again this is a front panel. This is the heavy OEM cotton pad that you will remove and place aside when you apply the great stuff foam to fill the large void area, as you can see that’s been already done here.

This is is a back panel. Notice the added great stuff to the styrofoam piece. Above that is the other pad you would use fuze it to glue to the panel to keep in quieter.

This is the 100 mils felt

Rear door covered with both the visqueen & felt.

Lightweight black with a single coat of contact cement.

Door panel with two coats of contact cement

Lightweight black installed on door panel.

Edited October 16, 2019 by Last Indian
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[JUSTA6]

Always wondered (after drooling over what you CAN see on your car) How much was involved with watcha can't see.  So I'm not surprised.  Great story Gary and very helpful.

[Last Indian]

1 hour ago, JUSTA6 said:

Always wondered (after drooling over what you CAN see on your car) How much was involved with watcha can't see.  So I'm not surprised.  Great story Gary and very helpful.

Thanks my friend! Like pretty much everything else, it’s what’s underneath that counts! Or at least counts as much. Or the devil’s in the detail!

Edited October 16, 2019 by Last Indian