Corroding is one of Aluminum’s favorite activities actually… White fluffy corrosion…which actually winds up protecting the remaining Al-Loo-Minium.
Difference between corroding and rusting. How do they say it over the pond? Aluminium corrodes but doesn’t rust. Now I don’t know how to pronounce it. Nuclear, nucular, either. ither. Forget it.
You mean fuhget about it. stainless steel rusts or whatever, plastic is better imhop.
Yeah I know. But now I’ll be danged if I really know how to pronounce it. The bank teller wanted to know where in Mexico I was going and I said danged if I know? I can’t pronounce it or spell it.
Rust is specific to iron and steel. Corrosion is a generic term that affects all materials. Aluminum will corrode but naturally reacts with atmospheric oxygen and forms an oxide layer that helps to protect from further oxidation. Stainless steel is rust resistant in much the same way as aluminum protects itself with an oxide layer, but not impervious to rust under the right conditions…
Check the post directly above yours. 
Several Europeans I knew in school pronounced it al-you-min-ee-uhm which accords with the international spelling of aluminium. U.S. spelling often omits the second i for the American spelling of aluminum, typically pronounced as ah-loo-meh-num.
Switch fasteners? No, switch locations. Get away from salt or buy a different make.
My old minivan was never driven in winter during salt season for over two decades and ditto for my Grand Prix for nearly that long. Both reside in Florida, now… no rust on fasteners or anywhere… Voila! Feel the magic!
If you live in road salt country or drive a car vulnerable to rust then you will have rusty fasteners.
CSA
Just consider rusting screws as SELL BY dates.
A lot of us light airplane owners have changed out our exterior fasteners for stainless ones. These are sold in a kit form.
These kits clearly state that the kits do not contain structural screws. Just like you said, TwinTurbo, a lot of engineering goes into the design of structural fasteners. Changing materials on a structural screw can spell bad news.
Stainless is the only option. Even Parkerized, Zinc, or Cadmium will rust after a while. That’s a of fasteners to change on a daily driver car for a lot of time, money, and so on. The rest of the car would rust apart before the fasteners
- Galvanized Steel–Zinc is sacrificial. Eventually the zinc is gone and the underlying steel rusts. Sooner if the thin layer is scratched.
- Stainless Steel–Pretty good, but will rust in the areas directly touched by a steel screwdriver
- Carbon Steel–Rusts quickly
- Zinc Plated–This is the same as galvanized steel.
- Nickel Plated–Much tougher than Zinc or Chrome. Can be plated much thicker than zinc or chrome, e.g., .010 inch. Not quite as bright as Chrome, a little more gray, less silver, but you might not notice the difference if you weren’t told.
- Chrome Plated–Chrome won’t stick to much. To make it stick to steel, an intermediate layer of copper is applied. If scratched through the tough chrome, the scratch goes through the soft copper, too. The scratch rusts immediately, then travels under the copper and you see the chrome flaking off.
- Zinc dichromate–This the gold colored finish which started appearing around 20-25 years ago on Asian cars. It seems to be pretty tough.It’s a Zinc plating treated with a dichromate coating. I can’t remember ever having one of these seize or rust.
- Cadmium–They used to use this all the time. It was inexpensive and tough. In the 1950s bicycle fender braces were advertised as “Cadmium-plated” and never rusted. Now we know that it’s highly toxic and it’s no longer used.
- Nylon–my choice for certain things like outdoor fixtures. I grew up in Illinois in the 1960s and I can remember when new license plates came out every January, laying on my back in the snow with a cold chisel and hammer, cutting off the rusted/frozen plated steel 1/4-20 bolts. When they came out with nylon nuts and bolts it was a miracle!
Hope that helps!
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These vehicles dont have to worry about Oxidization as much as others… Stainless Steel…every one of them.
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Stainless steel fasteners cannot be made in higher strengths needed for structural things. Chrome plating will flake off and rust even worse. Zinc plated fasteners are both shiny and the zinc is sacrificial to protect the steel which is why it is used a lot. Lots of modern structural bolts are a dull silver colored. Seems like a kind of zinc but I don’t know exactly what it is… but it is very corrosion resistant.
No bolt is forever so just swap out the ones that are rusty with bright silver zinc plating, not the gold chromate, it usually won’t last as long. But ONLY swap out like for like. If the bolt is marked 10.9, don’t use an 8.8. If it is marked a 5.8, don’t use a 8.8.
If you don’t know what any of this means, do your research and learn what this means before you swap.
Does anyone know of like a database where I can look up the strength of the bolts for the, thread, and length, and then just go and buy some online? Lets say I did know the strength of the bolt, length, thread, what site can I buy them off of? I seem to be struggling with this. Is there like a collection I can get of common ones? I don’t want to spend like 7 bucks for a single bolt, if I can just get like a whole collection of them in like a tray. The service book for my car includes this chart. I ask because I have broken some bolts in the past that were rusted out bad, broke when trying to get them out. So I would just go to a car parts store and pay like $7 for a bolt. I hope I can like find a collection of them in a tray instead of just paying per bolt.
The “Bolt Store” you are talking about @john.smith0909123_160324 is called the “Salvage Yard”. Not sure where you are located but in my neck of the woods there are a lot of yards…some are Pick a Part yards.
If you have any pick a part yards near you…go…bring your tools and a couple buckets…and fill them up with…nothing but fasteners. I’ve done this many times over the years.
The automotive fasteners you will reap will last you decades…and they will be Grade 8 hardened fasteners. The amount you will be charged at the checkout will make you giggle if they even charge you… and the fasteners are invaluable.
This is how its done. Garages and mechanics all over the country have stores of bolts like this just from the work they do and projects they see etc… They build up over time, trust me. I have an Ocean of fasteners at my disposal…from projects and from my salvage yard escapades.
The only time I ever need to buy a bolt is when it is a very specific fastener…like the ones that exist on my CBR1100XX…it has these extremely decorative fasteners with a revolver looking top on them, they are beautiful and expensive…so…know what I did? Went on ebay and bought a “bolt teardown set”…someone disassembling the same bike…saves every spring, nut and fastener and sells them in a big pile… for very little money…now I have multiples of every fastener on my bike…internal engine bolts, exterior decorative fasteners…every single one… It would cost an absolute fortune to buy these from Honda one by one.
Use your head Fred…buy bolts from tear downs and or go to the yards… You will never need to buy a bolt again.
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Where do you live and drive these vehicles? Please indicate the general area. Is road salt applied to roads there in winter?
If bolts are rusting, badly, then other parts of the vehicle have to be damaged by rust as well.
When I lived in the road salt area for decades, and I’ve mentioned this on this forum for a couple of decades, every car I had to replace was replaced due to rust and not due to wearing out by mileage. I hated that, but it was just reality until I stopped doing that.
If you live in a zone of fairly high or higher than “normal” vehicle corrosion then you are fighting an uphill battle. I’d be very concerned about corrosion on parts and components other than fasteners, too.
If you live is such a place then I’d save my money for the next replacement vehicle when the ones you drive dissolve beyond what would be safe or aesthetically pleasing.
So, John Smith, where do you live?
And, are these daily driver vehicles, classics, exotics, or show cars?
CSA
Not sure if ( struggle ) is the correct word . So you buy a collection of bolts - your project will need 2 and you only have one - your project will need the one your ’ collection ’ does not have - your vehicle will die and the one you replace it with does not need any do it yourself work for years - by then your will not remember where you put the bolt collection .
John , I have to admit you certainly think of things that most people would not think of.
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