In search of a definitive solution

[vonVeezelsnider]

You are looking at a two and a half foot wide piece of plastic "chrome" that has been one of the biggest sources of frustration for me in the last five years. The Coles Notes on my tale of woe:

The trim applique on the trunk of my 2007 Impala is attached at the factory using six-eight clips into the trunk lid rather than an adhesive glue. As a result the trim is not fastened with equal pressure across the entire part and it vibrates as you drive or when you close the trunk. Unlike the Impala SS models which have painted/clear coated appliques the chrome on the more pedestrian Impala models have a sharp rather than dull lower edge across the bottom which during said vibration bites and eats into the paint. The problem is it doesn't stop. It eats through the clear coat, through the paint coat and through the primer down to the bare metal. What happens then? Rust just inside the bottom of the chrome applique in various spots where the trim is vibrating and interacting with sediments that get in since it's not sealed, but merely clipped in.

[vonVeezelsnider]

I've had the rust repaired under warranty in October 2009, and June 2011, and now after less than a year from the last repair it has arrived again. I talked the dealer into covering the repair one more time but I would bet any amount of money that A) it will come back again if left in factory configuration, and B) They aren't going to repair it au gratis next time. The car has just under 60k miles and is approaching five years old. I need some sort of solution that works to prevent the chrome from eating through the paint again.

As you can see in the above picture they carved out the bottom of the trim at the edges but now the rust just starts forming further inboard on either side. That was what the GM TSB on the subject instructed and that does not work as you can plainly see.

I already have an idea to solve the problem but I'd like to solicit some other ideas and submit mine for some "sober second thought" before I go ahead with it. I was thinking after they fix the rust that I could:

1) Take the applique off and put a narrow strip (~1inch) of 3M film along the width of the trunk where the bottom of the applique meets the trunk lid. This won't spoil the looks department and you probably couldn't see it unless you looked closely at the lid.

2) Spray some "PlastiDip" (clear rubberized paint) around the mounting holes in the trunk lid for the applique clips to decrease friction/vibration in those areas and to discourage corrosion there (wont be visible under the chrome when it's reinstalled).

3) Spray the same rubberized paint on the back of the applique to take the edge off of it when it sits on the car. Between the 3M and the rubberized paint on the back/bottom lip of the trim there won't be the same paint eating friction occurring and there shouldn't be a repeat appearance?

Thoughts, guys?

[z28luvr01]

1) Take it off, remove the rust, and touch up the bare metal parts. The rust doesn't look bad at all. Looks like it might come off with some cleaner/wax or some compound

2) get an SS molding and have it painted to match

3) install SS molding

alternatively, replace steps 2 and 3 with

2) remove clips

3) get some silicone adhesive and put a bead around each clip hole

4) get some 3M double-sided tape and apply in between the clip holes

5) affix your original molding to the tape/glue

[Robert Hall]

Here's how I'd approach it... do #1, then plug the holes (not sure with what), saw the pins off the back of the strip (the strip has pins that go through the holes to which the clips attach?), and glue the strip in place w/ super glue or some other strong glue..

[ocnblu]

I would take off the molding, repair the rust spots, then cut a piece of soft, weather resistant cushioning material just a 16th of an inch bigger than the molding to put between it and the lid, that will muffle the noise when closing the lid and keep the sharp edge of the molding from digging in to the paint. Two-sided 3M tape would do double duty as a cushion and adhesive.

Edited May 2, 2012 by ocnblu

[vonVeezelsnider]

(the strip has pins that go through the holes to which the clips attach?)

Yup... just like that they look like this (jacked from another forum)

When I went through this song and dance in 2011 I actually wanted them to do almost verbatim what you and Z have suggested, sawing off the clips, sealing the mounting holes, and sticking the trim on flush with adhesive but once they got the applique off the car they looked at the inside of the part, and showed it to me; it wasn't possible to attach it using adhesive and get it to stay because the applique is hollowed out inside about three quarters of an inch.

Basically despite what it looks like from the outside, except for the clip points, only the four extreme edges of the trim come close enough to the trunk lid to make contact with an adhesive or the 3M badge adhesive that the OEMs use. I was told that there wasn't enough of the part they could actually stick glue or adhesive on that it would be able to support the weight of the whole part during day to day use...

Of course what 'blu suggested about using the badge tape merely as a cushion between the two parts around the four corners is not a bad idea at all, that might be worth trying for sure.

Edited May 2, 2012 by vonVeezelsnider

[ocnblu]

3M two-sided tape is gray, it will blend in pretty well with yer paintjob, I think too.

[vonVeezelsnider]

3M two-sided tape is gray, it will blend in pretty well with yer paintjob, I think too.

I'll have to go to the 3M retailer tomorrow and pick some up. They're warrantying the rust repair next week so as soon as I have it back I'll have to get on it then. I'll have to get whatever the thinnest tape they sell, about a millimeter or so maximum as I don't think anything thicker than that will allow me to get the clips back in.

[daves87rs]

I would take off the molding, repair the rust spots, then cut a piece of soft, weather resistant cushioning material just a 16th of an inch bigger than the molding to put between it and the lid, that will muffle the noise when closing the lid and keep the sharp edge of the molding from digging in to the paint. Two-sided 3M tape would do double duty as a cushion and adhesive.

+1

[David]

Why not just remove it completely, weld the holes closed and repaint it to match the car or have a silver strip added there to mimic the original fake chrome strip.

[vonVeezelsnider]

I had my car in to the dealership today having the front brake pads done and the rotors machined down to get rid of a little brake pulsation and I happened to end up having a chat with one of their body shop managers and a body technician. He kind of discouraged the 3M double sided tape solution I pitched to him actually... apparently there isn't enough clearance between the body and the trim to get the applique back clipped in with the tape down, as is the case with anything that's 0.5mm or more mm thick apparently. The thinnest of the double sided badge tape is 0.8mm. Doubted the 3M film idea I came up with as well actually, while that might be thin enough to get the trim back on and potentially strong enough to prevent paint eat-through by the bottom edge of the trim, that would probably just trap water inside the area behind the trim entering from the sides and create different kinds of rot altogether.

Back to the drawing board I guess. They are going to check with a couple of people who have more experience in this department and get back to me on Monday but one solution they floated is probably more inexpensive and potentially deals with the solution.

1) Order a brand new piece of chrome trim that hasn't had the drainage points drilled and cut into it as part of the numerous rust repairs and TSB so it has a continuous flush edge fitting to the body.

2) Coat the back of the new trim and the lower edge in the clear plasti-dip spray to dull and shield the sharp edges that vibrate into the paint

3) Replace existing trim on the vehicle with the new coated trim

4) Use automotive silicone sealant to seal the top, bottom, and sides of the trim, all the way around so that no water gets in and out of the area in the future

[David]

Man I hate to say it, but is it really worth the time or is it better to just trade it in and get something better built?

[vonVeezelsnider]

I honestly don't think so- this is probably the only real issue I've had with the car in the five years I've had it. Just by my nature I'm going to obsess over these things regardless so better the one devil you know than the many potential ones you don't.