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Is there a reason why these two rotors look different?

They are both the same item number. Why does one have two raised circular lines on it?

Very odd looking, take it back to the store and get another. The machine marks on both indicate they are new but the one with the center line looks darker.

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This line is raised ? or is it grooved ?

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If it’s grooved, someone screwed up and installed a brake pad backwards. Then they returned it to the store, which put it back on the shelf without checking.


I agree with shadowfax and I flat don’t get the second one. Those ribs would keep the brake pads from making full contact with the rotor.

Unless there was some kind of CNC machining error and a careless person or two let the faulty ones get through is all I can think of. A friend of my son is a CNC machinist and he mostly turns out pistons. He has said that hiccups occur with the process sometimes but they’re usually caught and the defects are trashed.

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Agree with shadow. One looks new, the other looks used.

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Felt raised at first but second glance it might be the edges that I feel and might be grooved. The other ring is smooth and there is another ring in between those two that did not show in the image. These were from Amazon Warehouse marked as new, just damage to box. Returning it, just wanted to see what the rings are.

We use Amazon a lot , but for vehicle parts - not even going to do that .

Another reason why you don’t buy car parts over the internet unless part is hard to find, or very expensive.


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I bought few auto-parts from Amazon, but pretty much limited that to original OEM parts, which happen to cost less there than in other places.
Also, their return policies are quite good.
Still, I do agree with @Tester and @VOLVO_V70, Amazon is not the best for aftermarket/non-OEM things.

A coworker owned the Accord I now drive.

And when the speedometer needle started bouncing, they ordered a used instrument cluster off of EBAY and asked if I would install it.

I installed the used cluster and the needle still bounced.

They paid $100 plus shipping for the cluster.

Man! Where they pissed!

I went down to the local U-pull yard and got a cluster for $35. And it worked!

Live and learn.


Well, I’ve been buying car parts from Amazon since they started selling them. Never got anything I had to return or was disappointed in. Just replaced an alternator, idler pulley and a wheel hub with parts from them. Saved a bundle over local suppliers and even Rock on most of it. You can buy most suppliers including OEM. Of course I never opt for the cheapest. You get what you pay for no matter who is selling it…

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Since Amazon becomes a place for some unknown (and often offshore) sellers to dump their stuff, I’ve heard reports of counterfeit items sold there.
On cars in particular, I’ve seen that NGK spark plugs bought from Amazon was not exactly NGK, for example.
I tend to order from there if it is shipped directly from Amazon warehouse, for all marketplace items, I’m not so sure, so I better go RockAuto or local store

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Going to agree with @shadowfax

rotors are cheap online. as low as $20. but shipping is 10. which is still ok for total price

Buy a $20 rotor and I have a prediction for you. It’ll come in a white box and need to be prematurely replaced compared to a middle to upper priced rotor. BTDTBTTS. I bought some white box rotors once many years ago. The metal had some type of inclusions in it that were much harder than the rest of the rotor. This caused gouges in the pads and a lot of braking noise after only a couple of months. They were in the metal recycling bin and replaced with ones costing almost 3x as much but those lasted 70k miles…plus I had to buy another new set of pads even though the ones on the truck were essentially new but severely gouged. YMMV


I’ve always thought that Chinese metallurgy was on shaky ground. My opinioo is that they throw everything from car bodies to tree limbs and dead dogs into the kettle.

About a dozen years ago I needed a Metric thread die and mine was broken. The only option was a bric a brac store which was open on Sunday. They had a die but it was in a set of 6 along with the die holder. Better than nothing I thought.

The minute I started turning the die it crumbled into 4 or 5 pieces and the holder handle also broke. Both made out of some shoddy pot metal. Only the Chinese would make a thread die out of pot metal was my thinking. It all went to the trash bin.

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That’s an over-generalization. China has a lot of poor-quality products just like America does. They’re fully capable of making high quality products, but they are not going to do that if the American importer doesn’t pay them for it.

The whole reason American companies are going over to China to have their products manufactured is because they can get it done cheaply. If that’s the mentality, they’re often not going to spring for the good stuff while in China. “You get what you pay for” applies to goods sourced in Asia as well as here.

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The other reason is it is easier to sell in China if it’s made there.

We have manufacturing done all around the world. We’re slowly pivoting from our Chinese suppliers because of the tariffs. However what you say is true. You can pay for junk material or quality material. The one constant is less expensive labor. For example we can have a 2ft cubed tank machined out of billet aluminum block for half the price of a cast part. It would be 3x the price of the cast part if you had the same part machined in the US. We demand CofC from all suppliers for their materials used in our products to ensure they meet specified quality. Lots of companies use Chinese suppliers and use quality materials. It’s the inexpensive consumer goods that are more likely to use the cheapest materials available…

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These are Durago, are they considered low quality?