Justrolledintotheshop
Only 20k miles…
Front and rear diff service on a new(ish) Chevy diesel. How is it rusted this bad already in the front? Both differentials were quite low on fluid as well as very sludgey inside. Shitty dealer job? Shitty factory job?
Discussion
People in the rust belt dream of this rust
Bro seriously we get brand new cars off the transport that look like this just from delivery.
Yeah, because it's made to do that. The rust layer protects it. Seals the metal from any further oxidation.
Fun fact aluminum does this naturally. It oxidizes as soon as it touches air, but the oxidization layer is thin and ends up protecting the rest of the material.
The diff fluid being nasty might just be from the truck being used hard and the diff being under a lot of stress frequently.
My 38 year old station wagon overloaded with like 1000lb of stuff, driving cross-country during a move. "I'm concerned the CEL comes on every time we climb a hill".
Aviation mechanic GF at the time "it's probably just the transmission overheating because we're pushing it so hard."
1200 miles like that, probably should change the fluid again even though we did it mid-trip.
Not too concerned, you can still get rebuild kits and I want to get that done anyway.
In my humble opinion-this is a nothing burger
Bro, Car Mechanic Simulator 2021 wasn't lying!
Nah I was gonna say this bitch looks like a 5% for sure.
It's car mechanic simulator in real life
Every day buddy 😂
Telling people you're down south without telling people you're down south
Florida lol
Come up North where extreme rust is considered normal. I would crawl under that truck, see that rust, and say, "It's not even rusty yet"
Absolutely nothing wrong with that
Unless metal is coated or is covered in oil or grease, it will rust, even if it is stainless steel.
I have received brand new generators with parts that look like this. This is normal for cars too if any of the parts are untreated
Depends on the stainless steel grade, 316L will definitely not rust in salty conditions, or even from detergents etc.
I’ve seen 316L rust out, but it was in a nickel refinery with VERY corrosive liquids everywhere
316L will absolutely rust in salty conditions. Thats why we dont use it in marine environments. Duplex 2205 is the bare minimum for marine.
Differentials have a bunch of scary looking fluid at their first service cuz they wear in. A little material wears off the gears as they mate together. I wish I did my first diff service at 15k not 60k like the manufacturer said knowing what I know now.
New mechanic simulator is looking really good
I do new car prep at a Chevy dealer from time to time and the axle shafts look like that off the delivery truck lmao
Regarding fluid level, someone missed it at dealership PDI. I remember reports of low fluid in diffs on forums when 1st gen Duramaxes in GMT800 were coming out, it's happened since then at least. Worth checking tcase as well.
Yeah bro stuck my whole pinky in both the fill holes and that shit was dry
Yeah, sounds like poor PDI. If I remember correctly on the GMT800s, if you put the exact quantity listed by GM in the gear boxes then you could barely feel it with a pinky. The old way of filling to the bottom of fill hole is actually "overfilling" it per the published amount it's not a lot, like less than a pint. 🙄 Whatever, on my 07 Classic I went to fill hole with my services and didn't have any visual issues with blowing seals or overheating and puking fluid from breathers.
That’s normal, just surface rust. Now, it it was flaking off, that’s when it’s a potential problem. I’ve seen rust like that on cars at their first oil change.
car mechanic simulator aaah looking parts
It's gotta be getting at least decently hot to rust that uniformly and quickly
Corten steel maybe? Rust seems too uniform to be just normal corrosion.
That's flash rust. It can appear on any clean steel surface. The cleaner, the more uniform the rust. These parts look like they missed getting coated with something
Flash rust is a very thin powder layer that wipes off with a cloth. This is most definitely not flash rust😂 you can easily tell by looking at the texture. Flash rust has no texture. It's a super fine powder....
Yep, that's a new car. Geetings from Kansas
This looks playful next to my Malibu I just scrapped because of rust
This looks like a Car mechanic Simulator
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I’m not a metallurgist, but I recall my friend having a Browning Mountain Rifle (Black Powder) that used this process in lieu of bluing.
All miles driven through the surf at the beach?
This is the kind of rust I wish I could complain about
Not corten or any HSLA steel. This application is a thick forging (? I doubt cast) completely unsuitable for corten. Every example people listed is bridges, building, or containers that a sheet or structural (welded) fabrications. I agree unpainted as cost savings and everything else will fail before that part rusts through. Find a citation with corten used for any automotive drivetrain component and prove me wrong.
Corten is relatively expensive. This is GM. Rust itself slows the rate of oxidation and when you have a thick, cast piece like this, my bet is that they just left it raw because it will take a loooong time to rust through. They figured they could save $0.15 in paint and time because it won't be an issue until it's way out of warranty. I see a lot of brand new CV axles rust like this, too. I think it's cost reduction. But hey, maybe GM let the engineers pick this time.
These sort of parts rust even when painted. It just takes a few months before they start doing so in that case. They're made of steel that's intended to develop a fine layer of rust like that.
Corten steel isn't recommended for salt spray environments. In fact, quite a few municipalities have revised their criteria for use on bridges based on exposure to de-icing salts. (National Cooperative Highway Research Program report 314) {https://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_314.pdf} Ductile cast iron has good corrosion resistance due in part to the graphite nodules in the metallic matrix forming graphitic surface layers. It is dirt cheap, strong, and casts extremely well. I'm not saying it isn't Corten, but I am saying the assertion that it is lacks rigor. I also know how GM operates, at least in the context of their 1500 series trucks. Source: former colleagues who may have designed some of these parts. I'll ask 'em
This is Chevy's definition of perfection...
It's called Corten steel, it's designed to quickly make a rust layer on the outside of the metal which actually protects the inside of the metal
This right here. Needs to be further up. Annoying as it may be, that rust is the same idea as those rusty bridges they make today. The metal is made to rust to protect itself. It ain't pretty, but it's functional.
There's a pedestrian bridge in my hometown that they built and it rusted within a year or so. So many people were angry that the city let it rust like that and cheaping out on materials. They basically were just like "did you not read the info we put out about this before we put it in? It's designed for rust." I honestly really like the look of it.
A709 :) :) love it!
Hello my fellow metal man
What’s going on! Stay true!
Not me thinking you were both British and from the same town and the bridge was on the A709…
lol! You’re a smart one trying to find context when I didn’t leave any. Your Pattern recognition skills are strong haha
It’s a boring metallurgical type nomenclature for bridge weathering steel.
I’m more of an A588 man myself
I’m more a A113 or element 115 man myself…
Element 115 you say?
Oh the paths that opportunity brings us
Probably A847 if it’s a pedestrian bridge, that’s the tubular products version. A709 is structural shapes, which covers all of the Wide flange beams and the like.
Thanks for clarifying
Like the footbridge between the train station and the new bus station in Stockport
The amount of customers who have to be taught this is maddening. If it wasn't supposed to rust it would be covered in some ungodly, uncleanable wax or grease.
On
Functional is pretty.
It's way prettier than paint with holes in it
A little wax does wonders. Edited because it made no sense
My CDs have never sounded so good.
Cor-Ten is the same steel used in the construction of the US Steel building in Pittsburgh.
Also shipping containers, I'm pretty sure.
I always wondered what these stickers meant.These containers at work say it is appropriate.
And the original LOVE sculpture.
Well, it’s a US Steel trademark, so that makes sense.
Also known as weathering steel. It's used in architecture and power poles and things like that. My welding instructor at tech college told us about a building he worked on where they used this steel(which was significantly more expensive at the time) between windows and above and below the windows was painted white. Interesting in concept, but anyone who knows anything about rust should know how it turned out. A couple years later they painted the whole building white because the rusty steel stained the white paint.
Never knew that was a thing, thanks for the info!
Also commonly used for shipping containers, because they're painted but they get banged around a lot so they don't want them to rust through where paint gets chipped. You'll see stickers in them that say "use Cor-Ten steel for welding"
This applies to all metal oh my car in the rust belt, right?
This. Thing is that it eventually will rust completely. The first layer will peel off due to wind/sand or other influences and the cycle continues until nothing is left.
Some driveshafts have a more normal steel core for reinforcement; meaning if the corten is gone it’ll rust out like anything else.
Weathering steel isn't invincible, and if exposed to water or salt for long periods of time it'll rust just like everything else. A bridge in Pittsburgh (Fern Hollow bridge) collapsed because of this.
Watched an interesting video about this. The collapse wasn’t really the use of the steel but improper maintenance and drainage. It let water build up on the interior of areas it was never meant to be. If I remember correctly it was only designed to last 50 years so it was due for replacement even if properly maintained.
In the end just an example of poor maintenance and the overall decay of US infrastructure.
I gave a talk about this bridge. It was the continual can kicking. If everything is low or medium priority nothing ever gets done. They perpetually downplayed basic maintenance. The moral was even low priority stuff has to get prioritized so they don’t become problems themselves.
That’s interesting. I’m pretty sure it was the YouTube channel plainly difficult. Neglecting basic maintenance and passing the buck seems to be a very common cause of structural failure.
The alloying in weathering steel helps to suppress pitting corrosion specifically, and if left exposed will actually resist the delamination failures you normally see in structures rusting away. In the right applications it can have a similar service life to low coating weight galvanized steels at a much lower price point, and with much less cost to weld.
Thats cool. Make a cars enemy into your advantage. What is the longetivity versus painted part? Paint surely gets worn out there.
I find this interesting. Normal rust tends to spread deeper into the metal until there's nothing left but rust. How does this rust layer protect the underlying metal?
Will applying an oil based coating to this rust layer provide more protection or is it not necessary?
Details here
Doesn't corten mess up the corrosion protection of adjacent parts and seize bolts?
I asked my dad (an engineer who has to know about steel properties for his job) about some stuff that looked like this. He said it's steel that oxidizes like aluminum. It oxidizes pretty quick, but is just surface rust. It doesn't penetrate.
I would imagine it’s self healing to a degree, as in if you scratch it the corrosion will fill in the space.
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You expect A mechanic to know metallurgy? They turn wrenches. Hell most welders who have never seen it don’t know what Corten is