[Razorback7]

My M2, along with a Macan S, are the first vehicles I have owned with lots of aluminum bits, including suspension, underneath. To keep clean I hose off at each hand wash best I can and now and then also hit with a mild degreaser then hose off. The BMW does not see snow and salt but the Porsche does occasionally. After 1 year and 2 1/2 years respectively, all looks pretty good. Do the aluminum parts tend to oxidize a little and darken over the years? Are there upsides (or downsides) to hitting the parts as best as possible without a lift or jack with anti-corrosion spray such as Corrision X maybe once a year or so? Thoughts/suggestions? Thanks and happy turkey day here in US.

[tke743]

I wouldn’t worry about it. Aluminum in practice is highly corrosion resistant. Counterintuitive as it sounds, it’s corrosion resistant because it is so easily oxidized. When aluminum is exposed to air, water or most other corrosive environments it oxidizes immediately to a layer of aluminum oxide. This protects the metal from there on out. The layer is quite resistant and is called corundum, (its other name is sapphire). It’s one of the hardiest substances know to man.

If the layer is compromised the newly exposed metal will immediately create a new oxide layer.

There some exceptions, if it’s in an electrolyte solution (salt water) in the presence of another metal and the oxide layer is compromised it will pit quickly as this is basically an unintended battery. So rinse it occasionally during winter. Also (no matter how unlikely this situation is) never let it be exposed to anything with mercury in it, as the mercury will literally degrade the aluminum before your eyes.

[ZPrime]

Mercury + many metals = amalgamation. It doesn't actually "eat" the metal, they combine and change.

[Cibbersicks]

I've coated mine in ACF50 - it's used in aerospace for protecting aluminium parts. It's fantastic stuff, ive used it on all my motorcycles over the years and has kept them looking new. Give it a try.

[Bee Pee]

Originally Posted by Cibbersicks

I've coated mine in ACF50 - it's used in aerospace for protecting aluminium parts. It's fantastic stuff, ive used it on all my motorcycles over the years and has kept them looking new. Give it a try.

+1 for ACF50