Removal of and prevention of filiform corrosion on aluminum wheels

[JWGreen]

I have a 2011 Dodge/RAM 3500 DRW with the Laramie/Longhorn appearance package which includes 4 Alcoa aluminum wheels. Painted steel rims are on each inside dual
wheel. About 2 years ago I noticed a whitish substance around the valve stem on the aluminum rims. Further investigation determined it was filiform corrosion. It occurs on the aluminum surface under the clear coat. Internet searches produced some possible solutions on removing the corrosion using penetrating oil and then using steel wool on the corroded area. The corrosion is actually magnesium oxide and originates from the magnesium that is a component of the aluminum alloy in the wheel. This method may remove the corrosion, however, the wheel will no longer have the clear coat that would prevent further corrosion or oxidation of the aluminum itself. Over time, the area will darken and require continuous maintenance. Does any one else have this problem and how have you dealt with it? I have asked my dealer to submit an inquiry to FCA customer service and we are awaiting an answer. Since Alcoa was the OEM supplier to RAM, perhaps they have a remedy. I'd like to hear from others who have this condition and how they fixed it. By coincidence, I have an Airstream travel trailer with an aluminum skin. Small patches of filiform corrosion have also appeared. Airstream suggests cleaning off the corroded area with a light pumice paste using a tooth brush. Then thoroughly clean the surface with isopropyl alcohol. They sell a "clear coat" pen similar to a wide felt tip pen with a clear coat in the reservoir of the pen. Apply the pen to the cleaned area. It seems to work OK but time will tell.

 

[Bob4x4]

I guess I have been lucky.I have never had this happen on my truck or my Airstream.The Airstream forums do discuss it a bit.

 

[WW101]

Though not near as heartbreaking, I have the same problem with the rims on the golf cart. My son who is well versed in metallurgy and machining advised me to strip off the clear coat, polish out the imperfections, then apply clear coat again. Other methods may look ok for a little while but do not remove the root cause of the problem. I haven't done it yet, maybe a wintertime project...

 

[JWGreen]

The Airstream forums thread is a few years old with no recent posts. I am planning to try using CorrosionX as suggested by one post. If it works, then at least I have a possible solution. I do plan to contact Alcoa to see what they have to say. My truck has been in the Texas Coastal Bend during the winter for at least 5 yrs. (December through March). My theory is that the climate there has accelerated this problem so I may have to change my winter digs. The "sea fog" is frequent and the salt air is very corrosive to other metals.

 

[WW101]

Do the Airstreams have a clear coat? or bare metal? curious...

 

[Jones2014]

Both of My Airstreams bought new, an 89 and a 2001 had the clear coat . Airstream buys the aluminum sheet from Alcoa When they first started doing the clear coat it was applied by spraying at the Airstream factory after the shell was riveted together then about 20 years ago Alcoa started to supply the sheet aluminum with a very tough clear coat applied at Alcoas factory This pretty much eliminated the earlier problem of the sprayed on finish peeling and dis coloring . The filiform corrosion is still an issue on the new ones . I was starting to have some on my 2001 Classic limited around the fasteners but after 15 years it was not very bad yet That is no longer a problem as last year we were rear ended by an 18 wheeler coming home from an RV trip and the insurance company totaled our very cherished silver twinkie thankfully my new Ram Laramie came thru unscathed .

 

[Newsa]

Are Alcoa rims made in China?

Edit: I might be mistaken.... I think its vision wheels that are made in China.

 

[JWGreen]

I have pursued this to a dead end with FCA and RAM trucks customer care. They acknowledge that the rims/wheels are Alcoa products but consider the information on the vendor or manufacturer to be "proprietary" and have said they can't (won't) help me get in touch with Alcoa to find their recommendation for remediation of the corrosion. They actually said my best bet was to do a Google search on Alcoa wheels. That search produces lots of seller but nothing from Alcoa corporate or the subsidiary that manufactures wheels. Anyone have a good source for Alcoa wheels manufacturers? My filiform corrosion is spreading!! Also, for what it's worth, I just had 6 new Cooper Destination HT3 tires installed on my truck with 92K mi. on the clock. Replaced Michelins with 45K that were down to the wear bars. Anyone have experience with Cooper tires?

Edit: The tires are Discoverer HT3 not Destination HT3, my error.

 

[Killer223]

i really like my Cooper tires. i have the AT3's and the ATP's, both will see 60+K good tire i think.

 

[The patriot]

My experience with aluminum being an owner operator for too many years, we'd just aluminum acid it.
It cleaned it, and made it uniform anyway. It was a work unit, so we weren't concerned with added work in our little bit of free time.

When I first got my UTE front bumper someone approached me about doing some sort of space age process QPQ type thing on it.
He said they could do different colors, or clear. Supposedly made the surface something like 90 on the rockwell C scale....or some jibberish like that.
I'm sure if you spoke with someone who deals with aircraft, or aerospace parts they'd know exactly what it is called.

 

[Learjet]

can you sand them down, re-polish then have them chromed or clear coated.

 

[JWGreen]

Does the corrosion reduce the strength of the wheel if left untreated? It seems to be a surface problem only. It's hard to tell if it has gotten into the wheel especially around the valve stem. I run about 75 psi cold in the tires, higher when they warm up. Any danger that a leak could develop around the valve stem from the corrosion? I'm more concerned about the safety aspect of this problem vs. a "cosmetic" issue.