Needs Transmission and Ride Quality Improvements - 2014 Mercedes-Benz CLA250 Long-Term Road Test
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Needs Transmission and Ride Quality Improvements - 2014 Mercedes-Benz CLA250 Long-Term Road Test
Edmunds conducts a long-term test of a 2014 Mercedes-Benz CLA250 and finds that its ride quality and dual-clutch transmission could be better.
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I think the suspension is the one area on this car where MB's inability to connect with younger buyers really shines through. Most of the time MB is perfectly happy to design cars for a, ahem, mature audience. People who value a smooth and quiet ride over most everything else. However, BMW's have always ridden really firmly and sold extremely well with younger people. Therefore, MB thinks for some reason that a stiff ride will draw in younger people. I think the fact that EVERY single review of this car has lambasted its suspension tuning and that it is turning out to be the number 1 owner complaint is causing Stuttgart to scramble. I would imagine the mid-cycle refresh brings some suspension revisions.
Also, "BMW's autobox" isn't BMW's at all. It was entirely designed and manufactured by ZF. It's a sensational gearbox (as it is in any number of Audi's, Jaguar's, Land Rover's, etc), but BMW certainly doesn't get the credit for making it so.
Completely agree with you, Jay. Well said!
I wonder if a refresh is even necessary... It's my understanding that MB already manufactures this car with a "normal" suspension, but for whatever reason they decided to only offer the Sport suspension in the USA by default. It should be as easy as MB deciding to switch-up the ratio of trims they produce, and start sending us the "normal" cars. I mean, they come off the same line anyway.
As Jay said, there's a difference between sporty and being stiff-legged. The trick is being compliant, but perhaps Mercedes really did tune the chassis like this in order to fool the gullible into equating bad suspension tuning with sportiness (like how most cars are ruined once you push their sports button). I'd bet they simply needed more time to hash the chassis and suspension out though.
And while ZF makes the 8-speed gearbox, ultimately it's up to each individual OEM to calibrate it.
@misterfusion,
Unfortunately the Comfort suspension isn't significantly better. You get more suspension travel, but the car still crashes over bumps. Now, this opinion is based on driving an A-Class with the setup, but they can't be all that different. On a positive note, though, I had the opportunity to sample a GLA and its suspension tuning felt quite good. I'm hoping some of that rubs off onto the CLA in the coming years.
@duck87,
Could be true, but that is very rare for MB. The chassis tuning is the longest segment of their development time. Plus, the execs boasted about the A/CLA's fantastic handling numbers from the start. It seems intentional, simply tone deaf.
I still don't know why anyone uses a DCT in regular cars. They're great in high performance cars as a modern replacement for manual transmissions. Lighting fast shifts and manual control for the driver. However for everyday use a traditional auto is much better. Low speed power delivery and smooth shifts are more important than rev matching downshifts on the drive to and from work. And I don't think BMW has ever made their own auto transmissions. They used GM Hydramatic transmissions for many years and now use ZF. Actually very few car makers manufacturer their own transmissions. Most are supplied by ZF, Aisin, Jatco, and Borg Warner. I think GM is the only car company that sells their auto transmissions to others.
Can't wait to see how good the new Hydramatic 8-speed transmission is in it's debut in the Corvette. GM promises better performance than a DCT. Considering they invented the automatic transmission they should know what they are talking about. But then, they still haven't mastered the ignition key.
The primary driver is fuel economy, mainly due to the lack of torque converter and better mechanical efficiency of the gear engagements. Other than that, packaging and weight control are usually superior, and there's also more control in ratio spread. Then there's the performance improvement you mentioned. It's not just drivers of ultra-high performance cars that appreciate fast shifts and good manual control.
Lastly, with all of the current technologies that are currently being explored to increase efficiency, most DCTs lend themselves to better integration. Getrag, for example, has developed a system where the pump for the actuation system doesn't draw any energy when unneeded.
Very true, such is the modern world. However, with the current competition and technological progress, many of the bigger OEMs are in joint ventures with suppliers to really push development. GM and Ford are also in a co-development transmission deal. It truly is a global world in the automotive industry.
Thing is, the ZF 8 speed really closes the gap on the efficiency front while offering lightning quick shifts while not having that herky-jerky nature that DCTs struggle with in stop and go traffic... and unlike most DCTs it can take quite a bit of torque. The transmissions are actually really compact, especially the 9-speed transverse version.
@duck87: Closes the gap is exactly right. It isn't as efficient as a DCT, but it doesn't need to be. Smooth shifting is incredibly important to the luxury segment and NA market, so the small difference in efficiency between the two doesn't hold as much weight, especially considering that the 8HP replaced 5 and 6 speed transmissions with great returns - more than enough for now.
I guess that the reason this conversation came up is because we're questioning why Mercedes-Benz didn't use something like ZF's 8HP. I'd venture to say that the biggest driver was cost, then fuel economy (MB felt this market was more sensitive to that), and then weight.
@quadricycle,
MB, like GM, is one of the only automakers left that designs and builds its own torque-converter automatics so they obviously were going to be looking for an in-house solution. However, the 7G-Tronic (and probably the upcoming 9G-Tronic) weren't designed to work with transverse engines. As a result, they had to come up with something totally new for the A/CLA/GLA/B. The DCT was probably cheaper to design and build.
@mercedesfan: Ah, while I knew that Daimler developed their own transmissions for their "big cars", I didn't know that they kept all transmissions exclusively in-house. I agree that the DCT implementation was probably easier and cheaper.
As for the 9G-Tronic, you're correct, it will indeed be for longitudinal architectures.
If Mercedes was trying to keep costs down then they should have bought one of Aisin's 6 speed FWD automatic transmission and saved money, lots of money, on R&D and building them. The average CLA buyer would be very happy. Not to mention that it is virtually maintenance free and very reliable. GM and Ford now build automatic transmissions together. GM will is working on the 9 speed FWD automatic and Ford is working on the RWD 10 speed. Together they can save lots of money and bring two transmissions to market faster. Most Ford and GM cars and trucks sold today use the same 6 speed transmissions.
At least when referencing the CLA and what it could possibly use, it's because the 8-speed ZF is longitudinal only. For the CLA, it would have to be ZF's 9-speed, for which the few automakers using it seem to have some trouble calibrating.
@allthingshonda,
Yes, but your are ignoring the arrogance factor that controls most of what Daimler does. They could absolutely have sourced an excellent transverse gearbox from Aisin, but why would they when they could build a better transmission themselves? Now, obviously they didn't build a better gearbox, but I'm sure that is what they were thinking.
MB a BIG mistake on this one, it didn't make the buyer pay for pain. Witness the Chevrolet Corvette. Although it is a billed as a sports car, if you REALY want a sports car the Buyer must pay an additional $4,000 for a "Z51" performance handling package, ie, a ride so stiff it will knock your fillings out. How dare Mercedes "give away" their sports suspension package for free in the base price! And then have the nerve to only charge $500 more for larger wheels and summer handling tires, don't MB know they are supposed to charge $2000 more for upmarket wheels/tires like the Corvette??
Mercedes made no secret of the fact that it was bringing this car to the US to attract a younger buyer. They saw how many young buyers opt for speed accessories, so they make the most important speed accessory, sports handling, free, and look what happens: every automotive journalist in the US spits in their face.
As for the tranny, I hope MB brings out a CVT for the journalists afraid of loud clunks and abrupt shifts, and include a rubber donut for the seat as part of the "press comfort" option package. And don't worry about Benz correcting their mistakes; as I was picking up my CLA 250 my dealer told me the standard passengers' electric seat is out for the 2015 model year. Just like the (C6) Corvette ZO6, but Chevy told the press that was to save weight. Given MB already has it's cost cutting knives at work, why would they continue to put a premium suspension on a loss leader car, especially when the journalistas try to convince the public it is a bad thing.