Why do car manufacturers make so many changes??
 

I have a W124 and was looking at newer MB diesel cars. It's like a game of Twister as to which ones are good and which ones aren't. For example the frog light headlight cars were ok if you got the 6 cylinder 1996 model, but the 1997 and 1998 had bad transmission problems.

I hear the cdi's are good cars, but the bluetecs could be problems. I know on some Volkwagen cars they had certain years where the power windows would fail around 30k miles. How could VW not have known this when they were making the cars? Just as soon as you know what a good car is (because it has a long enough history to judge it), they've stopped making them.

How can a manufacturer make something and change the designs every 2 or 3 years? I've read on some Mercedes they have sensor problems. Who wants sensor problems??? I know there are govt EPA standards to hit, etc. but there's too much instability. If they stuck with the same platform, found problems, and IMPROVED on those problems that would be good, but they don't. Instead they just make a whole new engine. It's got to cost them a fortune just in design and retooling costs.

Probably they do it so people keep buying new cars...since it is harder for home mechanics to keep them alive if they keep changing all of the systems every few years. Also to keep up with other car makers who keep making improvements (changes).

I hear Lexus is slow to make changes, which is good
 

But even they have problems.

It is primarily driven by MPG, emissions, and crash safety. The regulatory goalposts keep moving. With electrics on the rise, that could change. Keep the internals consistent; swap parts as needed. Change the body styling for style trends over the years.

Don't forget the NHTSA requirements. I understand over next few years we will see a system that tells you you have left a child in the back seat and walk away from car.

Moores Law
 

Cars are solidly now in the realm of high technology, and as such, will need continuous updates to remain viable in the market place, just like phones, computers etc.

Buying a new car today outright, makes no fiscal sense. The old rule of thumb for a new car was an ROI in 10+ years. Can you see yourself owning one of these new cars for that long? Without a warranty? The biggest issue is the extremely high amount of electronics in these cars that will be out of production as soon as the model ends, and are extremely expensive. So while you may have a perfectly mechanically reliable diesel engine powertrain...a PCM has you stuck in limp mode, is hard to find and costs north of $5k if you do. This maintenance cost structure pretty much ensures a very short product life.

Just for the sake of example, in my observation there are slightly more OM642 parts that have gone NLA than there are for the OM603, 20 years its junior. Hard to say definitively which of the two will be supported longer, or for how long.

My parent's Ford Escape already does that.

As someone who works as a design engineer I can be of some help, even if my industry isn't as big or as quickly moving as the passenger vehicle industry.

There's a constant battle going on between three teams: marketing, management and engineering. Every company is going to have this struggle, but depending on the size of the company, the size of its manufacturing base and the share of the market the struggle might look a bit calmer.

Engineering wants to make beautiful stuff. We want it to work well, do everything it was intended to do and never come back for a warranty claim. We really want to build to the scope document (which listed everything that marketing said they wanted this thing to do). Its a tough job sometimes to meet what was was asked and within the timeline expected, but engineers like challenges.

Marketing wants to be on the market faster than anyone else, they want to get the publicity and the sales for being first and better than everything else out there. Time is money and being first means you might get a bigger market share. Imagine being the first one out there with a color TV and months ahead of everyone else.

Management has to struggle to keep marketing happy and drive engineering to complete on time and under budget. But there's always a hitch. Marketing finds another feature midway through development that they want to add, or they want the product ready six months ahead of time for a different trade show, or they start selling a product before the agreed upon date.

So suddenly engineering has to start guessing, something we hate to do. We have to hope that the testing was sufficient, that the designs are good enough to go right now and that our first round of calculations were good enough. In short, we have to cut corners where we'd rather not and lower our standards where it might be safe to do. Sure, this means that we're going to have to baby this product for the first year, catching all the mistakes and longevity issues that we ran out of time to test for. And sure, this means a bunch more warranty claims (which, if I haven't mentioned, we hate) and a less perfect product overall.


The revisions and updates you see are the stuff that couldn't get caught prior to production because marketing pushed back on dates and widened the scope of the project. I'm in engineering so I don't care if the project takes longer if its perfect, but I might never be satisfied with it. Marketing wants it to be out on the market yesterday, but they trust engineering to get it right even if engineering is saying its not going to be. Management has to be the referee and tell marketing what isn't realistic and tell engineering what must be done by what date.


I know its irritating to have a million updates and different versions of the same vehicle, but you could look at them in a positive light. The company isn't willing to let a mistake or problem continue to exist, they'll still spend money to improve a vehicle/drivetrain throughout its sales life and a bit beyond (as long as that improvement is cost effective).

Matureo
 

Matureo, You made a good analogy of things but like I was saying, if the companies were to see a mistake on something and make it BETTER, that would be great. But they don't.

Take a look at the W124's. One model year has a wiring harness that goes bad, another has a head gasket that goes bad, some years have a cabin filter and previous models don't. All for the the same car with model years of 1987 to 1995. What genius came up with the idea saying "Ya know, the wiring harnesses are working out perfectly. Let's change them." ??? I could see if it was the REVERSE of that, saying the wiring harnesses have been bad, let's make them better. But they didn't.

Same thing with these stupid touch control radios and GPS systems in cars. I've seen many of Doug Demuro's (and other) videos where people can't even figure out how to turn the volume up on the radio; you have to read a manual and try to figure out all the steps to do simple things with it. What genius came up with the idea of having people driving along at 70 mph while they try to figure out how to change the volume of their radio?? If the stereos and GPS systems were that hard to figure out, car companies should have stuck with the tried and true. If Mercedes felt left behind because all the competitors went with these touch screen devices that everyone hates.... who would have looked better in the end? Mercedes would have. And who would consumers have trusted more in the future? Probably Mercedes for providing a stereo that humans could actually use.

These manufacturers trying to "keep up with the Jones's" isn't where it's at. Lexus is slow to make changes so they get to see what works and what doesn't, which has given them a reputation of not being first to market, but of taking a wait-and-see approach and therefore having very problem free cars.

But you're comparing different engines as if they were the same. That's not really a fair comparison.

I think you're referring to the biodegradable wiring harness and that was probably pushed by marketing as a way to make the vehicles more eco friendly. It didn't work out and they've gone back to the older design. Not all improvements end up working, it just the nature of new design. DeMuro is an entertainer. Please don't take notes from him.

Lexus tried to copy Mercedes back in the 1990s and they did a pretty good job.

Sure, you can wait to get something to market until after someone else is out there selling it, but that's going allow them to get a larger share of the market. You'd be surprised at the number of people who will buy a new technology/design when it first comes out. People don't wait until something is on the market for a number of years until the kinks are worked out to buy it. By then something else has been released and you might be buying something which is becoming obsolete.

I do think its rather funny for someone on a Mercedes hobbyist site to criticize Mercedes for not being Lexus.

I recently took a test drive in a new lexus. At 80 MPH, it felt like the car was riding on jello......every bump and dip in the road felt like we were riding on four sponges..... we had to slow it down so I didn't throw up.....

We are already there.

a 2020 silverado I use often (family truck) has a system that if you open a rear door (e.g. to put something there), the truck will have a message in the instrument panel display to check rear seat when you switch the ignition off.

on new benz I think they actually have occupation sensors on the rear seats too.

(how daft is the driver now that they forget about something in the rear seat)

Toyota has been doing this for decades now. Mercedes used to be like this till the early 90s, then the "green stuff" happened which entailed new technology like biodegradable wiring harnesses and water borne paint.

The main changes are in styling, like body and interior. They have to match trends. Look how many new cars now have the flush door handles (even motorized) and iPad-on-dash of Tesla cars. Plastic Headlamps must match the latest eagle-eye look, and full-width rear lamps are now popular (like 1960's Cougar). Underneath, the working parts can change amazingly slowly, and tend to follow each manufacturer's approach, despite the bodies all looking similar in any year. As example, the GM and Chrysler small-block V-8 engines changed little from 1960 to 2000, with even heads, blocks, and transmissions sometimes interchangeable. Ditto for the straight-six Jeep engine. But they also make changes which prove disastrous. An example I know is the Chrysler 2.4L DOHC engine (my 1996 minivan) was changed to a smaller crankshaft thrust bearing ~2005. Those wear prematurely, to cause the crank to move in and out and fail the seals. Did that save them $1 on each engine?

Tesla cars have the most screen button controls of any current car, with only a few physical buttons on the stalk and steering wheel, plus the mandatory physical emergency flasher button. A few weeks ago, they revised the screen menu to make it more like a web page, with a favorites bar for Netflix and games, replacing some critical buttons on the main screen, like "Wiper" and "Defrost". Not fun to browse the menus for those buttons while you can't see out the windshield. I think they are now 3 levels deep, under buttons "Fart-mode" and "Buy Crypto". Owners don't have a choice. If on a network, they get an automatic Over-The-Air update, so your new screen can become "disruptive".