Yes they have more issues with technology than other cars, but that's because they use more and newer technology than cheaper brands. [1]
Apparently with their vehicles (in this case a C180/2004) the tensioner is power-dependent and requires the vehicle to be used somewhat frequently to work at all. This means that simply by not using the car for 4-5 months, my dad returning to it and turning it on for < 3 seconds resulted in the motor starting with the tensioner not working, resulting in timing chain failure which irreparably damaged the valves and motor to the extent the vehicle was written off.
I don't have much automotive expertise by any means, but my understanding is that tensioner design in other makes of car generally do not experience critical failure when presented with "being used seldomly".
if your dad regularly lets a car sit for five months without driving it, he's going to have a lot of car troubles. ought to at least take it out a couple times a month, just for 20-30 minutes (ie, long enough to get fully warmed up).
I went to visit the shop while they were working on it. Wow, I do a bit of car work, but if I ever had my car in so many pieces I would never have gotten in back together again.
Thank god for extended warranties. I’ve never made out on a warranty so well, but one thing is for sure, I will never own that car out of warranty.
I'm not sure how reliable this site is but in general, it is accepted that most luxury German cars have reoccurring issues. The reason why I say "accepted" is because in most cases, they are pushing cutting edge technology and with so many parts, something is going to give.
I do not know common Mercedes issues but with BMW SUVs the most common issues are plastic parts near gaskets (leaks), electrical systems, and ventilation (especially in X3).
Of coarse there are exceptions and not all cars are created equal but this seems to be the consensus year after year.
I'm not gonna comment on the Mercedes because while they definitely have earned their reputation for being expensive in old age I'm not familiar enough with them to pass a value judgement.
There is a big difference in build quality and longevity between modern Mercedes cars and the ones built in the 1970s and 1980s. They used to feel substantially better than other cars. Now they don't really, except for the S class.
It also may be that because Mercedes and BMWs are "local brand" vehicles, there are more of them, and more mechanics out there able to service them? Whereas (to them) foreign cars like American vehicles you have to take to special American automobile repair places (like we have European auto repair places here that specialize in those makes/models)?
Again - guesses...
As others have said older Mercedes had very good reliability, so that probably still rubs off on how people feel about cars today. I'd consider BMW more sporty than luxury.
For instance, the base A-CLass (small/mid size sedan) sold in Germany has a 110hp engine and cloth seats, and very few standard features. Base price (w/o VAT) is ~$24,000US.
The base US A-Class has a 190HP engine, leather, more standard features, and starts at $32,500.
Of course, it helps that most low-powered cars sold in the EU will have manual trans, where all US MBs are autos...
Also, US buyers will run the AC a lot more, and AC eats a lot of power...potentially as much as 15-20HP... that's a lot more noticeable with a tiny engine.
The US is a mature product.
High end brands don't sell sub-lowend products.
That's been true for taxis in the US for a long time --- which are usually full-size Chevrolets and Fords. They're also much roomier and thus give a more comfortable ride than the average import econobox, with extra capacity for luggage.
There have been going down market in the U.S with the C class, then the CLA and now the A class, but these are still low-end luxury cars.