What is causing this to happen?

[GI Joe]

Started my new winter turbo project this week and noticed everything under my car thats aluminum is oxidizing and getting white mineral deposits and kind of powdery...whats causing this?

 

[Error404]

salt? where do you live?

 

[silverpoison]

Salt.........When I lived in CT I noticed that on my truck.....

 

[GI Joe]

no salt..Alabama...It stay in the garage...never drive it LOL

 

[cekim]

no salt..Alabama...It stay in the garage...never drive it LOL

Aluminum does not exist in nature. It exists as "alumina" or "aluminum oxide". It is actually rather difficult to get it to relinquish its hold on the oxygen bonds. Unless protected (or made into an alloy) it will develop a layer of oxide pretty much regardless but as you get closer to the ocean or any salt, there is salt in the air that will accelerate this.

The only way to stop it is to coat it with something that keeps the oxygen out.

 

[ArtQ]

If your garage is not "climate controlled" the change in temperature and humidity will also accelerate the process. Clear coat works well to prevent this.

 

[don_w]

Salt and/or oxidation is probably a better answer than magic pixie dust.

 

[Joe Cook]

Aluminum does not exist in nature. It exists as "alumina" or "aluminum oxide". It is actually rather difficult to get it to relinquish its hold on the oxygen bonds. Unless protected (or made into an alloy) it will develop a layer of oxide pretty much regardless but as you get closer to the ocean or any salt, there is salt in the air that will accelerate this.

The only way to stop it is to coat it with something that keeps the oxygen out.

 

[GI Joe]

I think it is the temperature change when I open my shop it all "Sweats"
No salt ever see's my car.

 

[cekim]

I think it is the temperature change when I open my shop it all "Sweats"
No salt ever see's my car.

Could be - it doesn't require much... How far are you from the coast? You might be surprised how much salt you see from the rain...

Again, though it doesn't matter, you just need to coat it if you don't want it to do that. I have been busy putting satin clear mid and high temp paint on everything as I build up. I am not one for blinging out my car, but I hate rust...

 

[GI Joe]

Could be - it doesn't require much... How far are you from the coast? You might be surprised how much salt you see from the rain...

Again, though it doesn't matter, you just need to coat it if you don't want it to do that. I have been busy putting satin clear mid and high temp paint on everything as I build up. I am not one for blinging out my car, but I hate rust...

I'm 250 miles...Its never in the rain either...but I would not know how to coat the things like the tranny pan and all...

 

[cekim]

I'm 250 miles...Its never in the rain either...but I would not know how to coat the things like the tranny pan and all...

Well, the tranny pan shouldn't get too hot - 300F as a ballpark top figure (hopefully it will never see that - as I recall most tranny fluid starts to fail over 260?

Others may have better suggestions, but I just used a satin clear VHT spray paint of the appropriate temperature range for the part...

The downside being that with clear paint, if you miss a spot, you find out later when it rusts while everything around it looks great...

 

[GRAYPNY]

You don't chew tobacco do you?

 

[PenguinGT]

You can get a can of Rustoleum clearcoat and go to town.