MAHLE also has an issue with counterfeit filters:
http://www.mahle-aftermarket.com/MAHLE_Aftermarket_EU/en/Examples
Originally Posted By: MAHLE
Examples from practice
TRADEMARK AND PRODUCT PIRACY HARMS MANUFACTURERS, DEALERS AND CUSTOMERS, BRASH PLAGIARISM AND POOR QUALITY FORGERIES ARE NOT JUST DANGEROUS BUT ALSO A GIGANTIC COST FACtOR: THEY EAT UP CAPITAL AND JOBS. NO MANUFACTURER OF POPULAR BRAND PRODUCTS IS SAFE FROM FORGERIES—INCLUDING MAHLE. BUT THE COMPANY HAS ITS WAYS AND MEANS OF PROTECTING ITS OWN TRADEMARKS AND THE BRANDS IT SERVES.
Counterfeit filters: It's all right until you take the wrappings off
A bonanza for counterfeit products. More and more dubious companies copy high-quality products of renowned brands down to the packaging – in the hope, to make easy money by illegally using good names and bad materials. As top-brands, MAHLE Filter and Knecht are not immune to counterfeiting.
Counterfeiting of automotive components is not a harmless crime but a real danger: the examples shown here are not only damaging to the reputation of the copied brands but also to the engine – and therefore to everyone in the supply chain who sells or is fitting such components. However, the counterfeits are not easily recognised – from the outside, the illegal copy is often inconspicuous. This is why our experts have looked inside of two rather impudent counterfeits.
Originally Posted By: MAHLE
The oil filter: The counterfeit is not operational
Tested and not passed
The filter, allegedly an OC 257, which a retailer sent to MAHLE Aftermarket for investigation, did initially not look conspicuous. After a simple scratch test at the printed label matters became more doubtful: the paint could easily be removed with the fingernail.
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At the left, the original with abrasion resistant printing. At the right, the counterfeit, where the printing could be removed with the fingernail.
Originally Posted By: MAHLE
Missing corrugation: cause for leakage
After opening the filter, a look at the end plate: in the counterfeit the second corrugation is missing. In the original, it serves to reinforce the cover plate to prevent distortion under load which causes the sealing ring to loose its sealing ability.
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The end plate from the outside: indistinguishable.
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But internally the counterfeit lacks the reinforcement corrugation.
Originally Posted By: MAHLE
Filter element: short and bad
Now the actual filter element: this is 10 mm shorter than in the original. This results in about 9 % less filter surface – and therefore less filter performance and reduced dirt pick-up. Furthermore, the element has only 60 pleats instead of 80! The lower number of pleats alone leads to a reduction in filter surface by 25 %. This means that together with the 9 %, the dirt pick-up is reduced by 34 % and the service life is reduced by 34 %.
Also the irregular pleat geometry is noticeable: sections of the filter paper are folded very tightly – just short of block forming. However, in other areas the distances are much too wide. Furthermore, the adhesive bond is missing at some areas between pleat star and metal plate, with the disastrous result that oil is here flowing directly from the dirty side to the clean side!
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At the left, the original, right the counterfeit: a shorter filter element and irregular pleating.
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In detail: the pleating is inadequate – and partly not glued on properly.
Originally Posted By: MAHLE
Anti-drain valve: not so clever
A particularly critical part is the seal between the dirty and clean side in the area of the anti-drain valve. In filters of the brands MAHLE and Knecht, the filter element is distinguished by a clean radius that, in connection with a precision moulded rubber part, serves as a perfect anti-drain valve. However, in the counterfeit filter, a sharp metal edge can be seen and the oil is flowing directly pass its sharp, cracked edge – without filtration – from the dirty side to the clean side.
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The original: a precision seal.
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The counterfeit with sharp, leaky metal edge through which the unfiltered oil can flow.
Originally Posted By: MAHLE
In the original, the anti drain valve is made with a precision moulded rubber part. At the right, however, the counterfeit with a simple, punched out rubber disk that does not fit tightly to the sealing surface.
The result: depending on the fitting orientation (filter fitted horizontally or on its head), the filter can drain entirely after the engine is stopped – and it has to be filled again completely at the next start of the engine. Until this happens, the engine is not supplied with the necessary oil (pressure). In the long run, this will lead to increased wear at the different lubrication points in the engine such as crankshaft bearing, camshafts or cylinders.
And there's more in that link.