Chinese made items can sometimes be of good quality, but only when the most stringent of quality control is relentlessly forced upon the (contracted) manufacturing companies. Otherwise, it is well known that Chinese manufacturers will take every possible shortcut to cut costs. EVERY short cut, including poor material specs, rudimentary machining tolerances, and incorrect processes such as rubber that’s improperly vulcanized, incorrect metal alloys… or metals not being properly heat treated or stress relieved. And that’s assuming the raw materials were correct to begin with.

What would you allow on your car? Like Dan said, there’s usually no way to differentiate the good from the bad. Even products from the exact same factory contracted to do production work for big-name companies are suspect. Those parts are not necessarily the same quality. For non-contracted production runs, they can (and oftentimes do) use inferior materials and processes to save every possible cent / yuan.

How about Chinese tires? Many big-name tire manufacturers are making tires in China now. But they watch things like a hawk; they are involved in every possible step in the process, from raw material procurement all the way to the final product. So while I may trust a Chinese tire from Goodyear for example, I would not trust some off brand private label tire produced by the “Sum-Rownd-Ting” tire factory.

Would you trust a Chinese no-name turbo on your car? Not me. Maybe if it was a TRW or KKK brand (etc.), with faith in the company putting their branding on the item and their reputation on the line. But then again, that’s no guarantee either. One only has to look at the Indian-made Bosch injector nozzles for the 617’s. The less said the better.

Putting some types of cheap Chinese crap on older cars is a surefire way to make them not get any older… because they’ll end up in the scrapyard.

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Current rolling stock:
2001 E55 183,000+ Newest member of the fleet.
2002 E320 83,000 - The "cream-puff"!
1992 500E 217,000+
1995 E300D 412,000+
1998 E300D 155,000+
2001 E320 227,000+
2001 E320 Wagon, 177,000+

Prior MBZ’s:
1952 220 Cab A
1966 300SE
1971 280SE
1973 350SLC (euro)
1980 450SLC
1980 450SLC (#2)
1978 450SLC 5.0
1984 300D ~243,000 & fondly remembered
1993 500E - sorely missed.
1975 VW Scirocco w/ slightly de-tuned Super-Vee engine - Sold after 30+ years.