Side Sills corroding!!!

[jay01m]

So I'm washing my car this past weekend, and noticed a big bubble from what I thought was paint caused by heat. Come to find out, my side sill corroded from the inside out and am on the verge of having a 1.5-inch hole in my sill. Over the past several months I've noticed the same on the opposite sides. Will post pics if I get a chance.

Has anyone else come across this issue? Is it fixable or am I better off buying new ones? Are new ones even out there, or is it worth tracking down some used ones that are in good condition?

For all you parts suppliers out there - Any of you have side sills for my 97 GTS for sale?

Thanks in advance,
Jason
Hampton Roads, VA

 

[JonB]

This is a well-documented issue that cost Dodge a TON of money, because rust-thru / corrosion warranty was 5-7 years depending on Model Year.

The cause is electrolysis in the insulation rivets and foil insulation, caused by road dust and film and water making an acidic, electrolytic bath..... I have see guys poke or prod that paint bubble and push right thru the sill!

Good ALUMINUM REPAIR places are hard to find.......the cost of new OE sills is grossly prohibitive

 

[dave6666]

...or is it worth tracking down some used ones that are in good condition?

Define good condition. I'm switching my car to side exhaust and depending on your response, may have a pair.

 

[FATHERFORD]

Mine is starting to do the same thing. Can't decide if I want to go side exhaust, or just repair the ones I have.

 

[jay01m]

Define good condition. I'm switching my car to side exhaust and depending on your response, may have a pair.

I would say they need to not have any bubbles that are an indication of corrosion. Anything else I anticipate being able to repair since I will be sanding and repainting it anyways.

Anyone thought of installing a sacrificial anode to avoid this from happening?

 

[jay01m]

Define good condition. I'm switching my car to side exhaust and depending on your response, may have a pair.

BTW - May I ask why you're going to side exhausts?

 

[dave6666]

Anyone thought of installing a sacrificial anode to avoid this from happening?

As the company I work for is heavily in to electrochemistry, I'll play expert here. Having a sacrificial anode on the sills would have some logistical issues. For an anode to work, something has to take the role of a cathode. That would be the aluminum.

When aluminum takes the role of a cathode it will likely create a protective barrier oxide layer, becoming a non-conductor, and therefore not a cathode any more. But the good news is that this oxide layer is usually a good corrosion prohibiter.

Bad news though... The sacrificial anode, if you can find the correct metallurgy to set up the aluminum as a cathode and the other as an anode, has to have close proximity to each other. In other words, your sill would have to have to 2 identical metal layers.

Sorry, but not practical.

If you wanted to put a DC power supply on the sill and force it to a cathode condition it would take some interesting design work also.

 

[dave6666]

BTW - May I ask why you're going to side exhausts?

1. Sills are cheaper.

2. Side exhaust is cool.

3. Burn the shoes of cops when they stand there trying to write me a ticket.

 

[mbccenter]

I do have a few exrta laying around.

 

[95Viper]

If / when you do repair them...strip all paint off and find a good aluminum welder to cut out and repair any corrosion. Do not fill, sand and paint. It will be back if all the bad stuff is not cut out.

 

[jay01m]

I do have a few exrta laying around.

PM sent, thanks.

Sounds like I should find a good metal fabricator to see how much it would cost to repair these suckers. I guess I should compare prices of buying new ones, used ones in good shape, or repairing my own.

Has anyone considered having the inner side of the sill sprayed with Line-X or Rhino lining spray to prevent corrosion? Would that cause clearance issues with re-installation?

 

[dave6666]

Has anyone considered having the inner side of the sill sprayed with Line-X or Rhino lining spray to prevent corrosion? Would that cause clearance issues with re-installation?

It would be great on the corrosion issue. But your gas mileage from towing a fire truck with you all day long would ****.

Urethane burns baby!

 

[FATHERFORD]

If / when you do repair them...strip all paint off and find a good aluminum welder to cut out and repair any corrosion. Do not fill, sand and paint. It will be back if all the bad stuff is not cut out.

Good thing I got skillz tig welding

 

[95Viper]

There you go...everyone with sill problems...ship them to Fatherford...it is impossible to find someone with tig skills.

 

[Ron]

Speaking of GENII's only and early ones at that, the root cause of sill corrosion is the unbacked sill insulation holding moisture (rain & car wash) and steaming the inner sills at every engine start. When you open the sills of newer GENII's (Maybe Jon B or Chuck can confirm cutover year) you'll find metal encapsulated sill insulation. This eliminated the primary cause of GENII sill corrosion.

The good news is that it's preventable if you catch it early and encapsulate your factory insulation. The bad news is that you can't purchase new sill insulation with out purchasing the entire sill. I had mine changed under warranty when the first bubble appeared and got the new insulation in the process.

 

[AHudson777]

I too would like to know the cut-off for the 'new' metal encapsulated sill insulation. Guess I'll find out sooner or later - have purchased the Roe insulation, planning to give the heat some entry/exit provision(s).

My side sills are roasting hot and paint has started to yellow at the exhaust bend.

Am curious if entry/exit holes invite the water damage we're talking about... or with adequate drainage provision this isn't a problem.

Not fond of 'solving' one problem (heat) just to 'create' another (corrosion.) Thanks for the input.

 

[dave6666]

Am curious if entry/exit holes invite the water damage we're talking about... or with adequate drainage provision this isn't a problem.

Not fond of 'solving' one problem (heat) just to 'create' another (corrosion.) Thanks for the input.

You are correct there is a balance between the 2 items. With all of the ventilation I'm putting in my sills (12x 2-1/2" holes) I'm banking on never driving in the rain, and drying the sills after each car wash by running or driving the car.

Of course having fiberglass sills helps too...