http://news.consumerreports.org/cars...-handling.html

What do you guys think of this??

Could this be fixed with a simple software update?

That is scary! I wonder if it is any better with Active Curve Management?

The quick answer is NO.... Active curve manages the "lean" of the vehicle in a curve situation....a gradual controlled process utilizing the suspension system. The issue that CR is talking about occurs with the sudden turn of the wheel left or right at speed causing the stability control to do what it's supposed to do ....attempt to bring the vehicle back in line by applying brake pressure to the side of the vehicle that appears to be sliding out of alignment. In this case, it is applying too much brake pressure relative to the speed and the intent of the driver causing the result you see in the video clip. Bottom line is .... It can be fixed or at least lessened by a recallibration of the stability control and, of course, turning the stability control OFF eliminates the issue completely BUT raises other issues that stability control was designed to deal with. Lets face it......large SUVS are never going to handle sudden serpentine actions very well but I am hoping that MB is able to make some adjustment.

When I pickup my vehicle 2moro I will raise this issue with the service department to see if they are aware of this, if not a call to MB head office will be placed.

Keep us posted on the response....... I would find it hard to believe that MB has not heard of the Consumer Reports findings by now.

Here's a good review that includes a section on the stability system and the issues that are part of this discussion.....

[URL="http://http://www.edmunds.com/mercedes-benz/gl-class/2013/road-test.html"]

"until Mercedes-Benz addresses it by recalibrating the stability control, we won't be able to recommend this very impressive vehicle"

I'll be curious to see how much MB cares about this evaluation, and what, if anything, they can do to rectify it quickly.

I'm picking up my 450 tonight and will be sure to mention it. I bet they aren't even aware of this yet.

Hmm, I would've expected the Active Curve System to help in this exact situation. Fact is, that's the main reason I've opted for it on my GL350, which I haven't got yet. It is also marketed by Mercedes as a safety feature, which I'd suppose would be due to its use in avoidance maneuvers.

There's a swedish car magazine that got a bit of international publicity when they made the original A-class roll over in 1997, something which initially was met by defensiveness from Mercedes, but which eventually made them include ESP (which then was more of a high end feature) as standard on the A-class to compensate its high center of gravity. Recently, they got a pretty bad result with the Jeep Grand Cherokee as you can read in english here: http://www.teknikensvarld.se/jeepmoosetest-part4/

Anyway, the reason I'm bringing this up is that they have a list on their website with the results throughout the years: http://www.teknikensvarld.se/algtest-lista/
If you click on "Hastighet km/h" you get the list sorted by maximum speed for the avoidance course. The current top model is a 1999 Citroën Xantia Activa V6 (kind of a standard car), well ahead of 2nd place which is split in three among some Porsches from recent years! Now what was so special about the Citroën, that made it beat a lot of sport cars? The "Activa" moniker is actually their designation for hydraulic anti-rollbars, similar to the Active Curve System (AFAIK)!

So, even though it won't transform a SUV to a sports car I think it should be able to help out in these kind of situations, although it probably could do better without it as well. It would be great to get some kind of response from MB on this!

The more I research some of this the more I come to this conclusion .... The systems on this vehicle are probably going to be valuable to us in 95% of the traffic situations we might encounter and thereby be a "lifesaver". In 5% of the situations it may in fact be counter productive! I am never going to expect my GL to drive through a slalom course like a sports car.......but if it protects me from most of the "normal" traffic errors that I might make ..... I'll buy it!

by all means if anyone has concerns than they should contact MB head office directly and let them know, the fix to this problem from what I see is software and not hardware which is a good thing, a 2 min reprogram is all it really needs.

I took delivery tonight and the dealer had no clue about this article/review.

When I explained the problem, his first words were "I smell a recall coming".

Well, being able to avoid something that suddenly appears on the road could mean the difference between life and death in a large class of accidents so I'd say it's not a fringe case.

I wouldn't expect the GL to handle like a sports car either, but I'd expect it to be on par or ahead of its competition. According to Consumer Reports, "Even some big, lumbering heavy-duty pickups we've tested recently have done better in that test."

My question still stands though, of whether a GL with the Active Curve System would be able to perform better. An official word from MB that they'll look into a possible recalibration of the stability control would be comforting as well.

Agreed! However, i do not believe the active curve system will make any difference ..... The sudden avoidance move activates the brake system causing the issue seen in the video ....the active curve system would do nothing to help keep the vehicle heading in the direction intended by the drivers sudden move
.....at least that's my understanding of how the systems work, but , there's gotta be some tech people on here who could confirm it one way or another.

what i'd like to know is that is there different esp tuning for different models depending on the weight of engine etc.. i mean if tuning is standard for all gls then will the gl63 have the same issue?

Just spent some time reading the manual with regard to the "Active Lane Keeping" system....... It appears that if the vehicle is equipped with this package, the system is supposed to recognize an "aggressive" turn of the wheel ( such as was demonstrated in the CR test ) as in an avoidance maneuver , and should NOT apply the front brake. I wonder if their test vehicle was equipped with the Active system or just the standard stability program??

maybe that info is in the full report which requires a subscription... anyone have access?

I read the full report using a friend's subscription. No mention of a reason for the poor handling in this test, but they do expect MB to come up with a fix for it.

Is this only for GL350 or for other models as well?

I would consider the source. CR has had biased issues revealed in their testing in the past.

my thoughts exactly

The CR report does describe in some detail their concerns for this issue. Here are parts of their conclusions:


Road Test

GL350 BlueTec V6

With a plush and hushed interior; relativelygood fuel economy; and plenty of towing capacity and interior space, the GL 350Bluetec is a cut above other large SUV. We found it to be the most comfortableriding SUV we've tested. But one serious flaw, reluctant emergency handling,gives us a pause.

Gasoline and diesel powertrains are offered; we opted for the Bluetec diesel because it offers the best combination of power and fuel economy. The 240-hp,V6 turbo diesel engine and super smooth seven-speed automatic transmission make for a refined and responsive powertrain, with strong mid-range acceleration and fuel economy of 20 mpg overall.

But the reluctant and unresponsive handling in emergency maneuvers is a serious problem. And until Mercedes-Benz addresses it by recalibrating the stability control, we won't be able to recommend this very impressive vehicle, even if this redesign proves to be reliable (the previous incarnation was not).



Handling: The GL is relatively agile for its size and bulk. It turns in promptly and the body doesn't lean excessively. The steering has some feedback even if effort is on the light side, but effort builds with speed and through corners. Although it's not sporty, it's surprising how much you can hustle the big Mercedes-Benz on twisty roads.

Pushed to its limits at the track, the GL's stability control kicked in early and aggressively, making it understeer to the point of running wide of its intended path. That severely limited the GL's performance in our avoidance maneuver, and the system's prolonged braking caused a tire to momentarily lockup. The result was a very low maximum speed of barely 45 mph through thecourse. This performance resulted in the GL earning a poor rating for emergency handling, and prevents it from being recommended.

has anyone contacted Mb directly about this? I told the service manager and he said no recalls or updates had come from MB

CR just posted their review of the GL350 the end of February so it could be another month or two before MB would respond. But a current owner of the 2013 GL should officially report CR's handling concerns to MB.

direct reportin definitely helps- my brother old 550 stalled a few weeks ago- no apparent reason, no cel, no codes, started up fine (it went literally lights out, everything off going 75miles an hour!!!) it then restarted fine, everything worked except, put it in drive or reverse and you hear transmission engage, and no movement, period! took it to our dealer, direct reporting done to MB, regional manager involved, entire trans replaced (at 50K miles only!) it has become an mb corporate issue.. being looked into at a large scale, they refused to let him back in the car due to safety concern, he didnt want to take it back either.. they repaired it, is just fine now, however our dealer is awesome- put him in a brand new 2013 GL, fully loaded for minimal price change and nothing down! so yea thank GOD having an honest awesome dealer and reporting to MB directly makes a difference. hes happy now... we should question MB directly about this