You can watch the Consumer Reports video of the GL350 if you are a member (I am a member and watched the video) but I found this link to an article about CR's emergency-handling testing that will at least give you a better sense of the issue:

http://www.autoguide.com/auto-news/2...r-reports.html

 

Their simulated test is not simply an avoidance maneuver. They try to get the GL to move from the right lane, to the left, and then immediately back to the right. The part it struggles to do is the immediate return to the right lane, they want it to be back in the original lane within ~ a car length. It has no problem avoiding the obstacle, it simply argues with the return to the right lane. I have some issue with their test though. How often have you ever even thought about such a maneuver? Moving over one lane quickly, yes, very much so. Moving back into your lane in such an aggressive manner is usually not needed though. Even if you did need to, it looked like it would take you an extra 1/2 car length to do so. Some fiddling with the ESP would likely enable the vehicle to "pass" their test but I suspect the ESP is activating to prevent a rollover situation, not necessarily something you want to be fiddling with. A rapid left/right jerk on the wheel at speed is an easy way to put a large vehicle like the GL on its roof. In that case I'd be much happier with the ESP intervening and keeping me upright but needing just a little longer to get back into my original lane.

There would be no difference, it's not a handling limit, it's a stability system thing.

I wouldn't hold my breath. I'd also watch the video and see the "flaw" for your self so you can determine if it is really such a dangerous thing or just something that a small percentage of people might run into. In addition, you should consider that the behavior is potentially more desirable than the alternative. Keeping in mind the GL is a big family mobile, preventing a rollover is much more important in most situations than getting a double lane change executed in roughly two car lengths

 

i agree 100%- also they dont really slow the car down either- i mean thats step #1 - slow down and brake!
think about it - even the 63 essentially has the same system..
i think its an appropriately safe feature and is to prevent roll over or turning back into the obstacle itself!

 

I agree...... I think (based upon all my reading and viewing the test ) that the vehicle is doing what the systems ( and their programers ) feel is the safest for that particular vehicle.

 

I don't think it is very hard to think of such a case; how about the case where there is oncoming traffic in the other lane? Besides, is their test very different from the ISO 3888 Part 2 (http://www.car-engineer.com/the-moose-test-or-vda-test/) test?
Yes, I definitely agree that it is better to keep the car upright, and if it would have lifted two of its wheels it would've failed even worse. The GL can't upheave the laws of physics, so of course it must fail at some point. The thing is, it fared worse than "some big, lumbering heavy-duty pickups" according to CR, which suggests the GL could perform better than it currently does without risking tipping over. Or maybe that's not the case and there is no problem, but since they've tried getting away with subpar performance in this kind of test before *cough*A-class*cough*, I think it would be a good thing if they'd address this.
Couldn't you say that it is a handling stability thing ? According to MB: (http://media.daimler.com/dcmedia/0-9...0-0-0-0-0.html)
Reduction of body roll will in turn reduce movement of its center of gravity, which should make it less prone to tipping over. I think the ESP should be able to sensor that and take it into account, but it'd be great if someone could disprove or verify this.
And Citroën's similar system sure helped them beat the original "moose test", as I mentioned in an earlier post...

 

In your first example, you're just in trouble. Personally I would never cross into the oncoming traffic to avoid something. My first action is to stop as I should have left myself enough space. If emergency action beyond that is needed, it should be away from oncoming traffic, not into. If i have to, I grit and let the car take the impact as it was designed to. Sadly not everything can be avoided.Comparing the GL to a pickup is still not a good comparison, pickups typically have a longer wheelbase than the GL and wouldn't tend to flip sideways and roll quite as easily. We just don't have the info to say that it is an overprotective ESP vs actually physical limits, that's MB's job. Potentially one could try turning off ESP and running the maneuver but if you are reaching the physical limits, you could very well end up on your lid. Not something many people would be willing to test. Yes, the active handling will help stretch the physical limits, but I'd be suspect of how much as it is just a very aggressive maneuver.

 

If stopping is an option, of course you would do that. Unfortunately, if a truck backs out in the street right in front of you or if a moose decides to run up in front of you, you rarely have the option to stop.
Secondly, of course it is better to run into a ditch than to hit another car; but suppose you don't have that option and you didn't see an oncoming car before you avoidance maneuvre. Most people would probably turn left if they thought that lane was clear of traffic, instead of hitting a truck or a moose. Moose (and deer, although they're not as lethal) often come more than one at a time and I've been myself in the situation where I'd had to "slalom" between a pair of moose.
Besides, even if you would never do this maneuver you could still be the one facing a GL struggling to get back into its lane.
I'm pretty certain that it is a bad idea to turn off the ESP, since the ESP can do things you can't emulate as a driver. And I totally agree that we don't have enough information to say that the ESP is overprotective and can be "retuned" or whatever to fix this. I don't agree with it being an unimportant metric, though, and I think it is a difference between reaching the conclusion "the GL is bad at this because it is a SUV, and SUVs tend to perform badly at these kinds of tests" (which CR didn't) and "the GL performs much worse than expected, in fact the lowest score of any SUV we've ever tested" (which CR did).

 

Another thing regarding this; it might not be you in the car that is in danger but whatever you're about to hit. Would you rather hit a child that's ran out in front of you, which most certainly would have lethal consequences, than turn left and possibly avoid an accident altogether?

 

So....other SUV's have completed this test with a higher score....all SUV's are not created equal in size, weight, power, ......run the big Infinity, Lexus, and last years GL through this and tell me how they differ......once you start adding computerized systems to the control of a vehicle, there WILL be trade offs ......after 200 miles in my new GL, I feel safer in this one than any vehicle I have ever owned...... I don't think my 94 Suburban or my 2000 Yukon would have passed their test either and neither of those vehicles were anywhere near as "safe" as this 2013 GL is in so many other ways. What I DONT want is MB to tune the system to meet the test but in doing so sacrifice stability safety in other areas.

 

scary video and no reply yet from MB?

Is this a scientific test?

Many unknowns.


1.They should get other year's GL s and test too. Also other 13 GLs.
2. sport or comfort mode?
3. 21 vs 19 inch wheels?
4.Adaptive damping yes or no?
and many more variables.

 

i had a similar situation today- except this was real, not a test- thank GOD this did not happen- presafe activated immediately- seat just holds and hugs you.. appropriate with handling and maneuvering- no unncessary wheel lock affecting steering response. I think in this video it more than likely was not done right or was an overcorrection which the car obviously didnt do- as I think it wasnt supposed to..

scenario was - freeway- without any warning boards or cones- there it was the big truck with the 'merge right' arrow- in the left lane going 5 miles an hour when everyones going 70+, 2 cars in front of me- muuuuch shorter distance to stop- needed to merge on left shoulder momentarily and then merge back onto the left lane..
yea- scaaaary! especially when the guy behind you is in a BIG truck going the same speed..
all i can say is thank GOD!!

 

Thanks GOD you are OK and the car performed as "advertised". This is a heavy car but I feel I am driving my S class 6 years ago (square body).

 

I am close to ordering a GL but this issue has me wanting more information... Can anyone add new information to the discussion? Please, no more arguing about the validity of the test, etc. I have been in a situation requiring just such a maneuver, hitting the object in front of me was not an option, and I was able to survive because the car I was in (300 ZX Turbo, fwiw) had the handling to allow me to complete the maneuver. I have also had to perform an emergency avoidance in a BMW X5 in which hitting the object was certainly a safe outcome, albeit expensive. My comfort level with the handling of the X5 gave me the reflexive ability to avoid the situation without incurring any damage. If I am going to be driving an $80,000 vehicle I want to avoid any trips to the repair shop! I like to think my maturity and driving style have reduced my risk; adding two children and a wife has certainly increased the cost of failure.

Thanks for all of the great information on this forum, and Happy New Year!

 

I would have no hesitation buying a GL regarding saftey. MB has long been a leader in this area. The GL has pre-safe breaking, cross wind stabization, etc. I did have to do 1 panic stop in my GL and the abs worked well and the car stopped quickly. I have owned a x5 previously and the GL doesn't handle as well or have the agility, probably because the GL is a good bit bigger. The GL is a big step up from the x5 overall

 

At about 50mph on a two lane causeway..I had a deer cross in front of my GL....
I hit the brakes and swerved... The vehicle in a split second tightened the seat belts and added more braking.. The deer made it across but still tagged me at the lower LED light section.

My buddy and I were blown away how well the car enhanced the avoidance tactics that I used. You can't get anymore real than that.

You can have confidence in the car for sure.

 

Revisiting this old thread started over a year ago. As part of my prepurchase research, I just read the CR report and evidently is was for 2013 model. Any updates on this issue for new model?

 

Don't know about that, but when I looked at CR's raw data they listed the GL as doing ~45mph through their maneuver. For comparison, a Porsche Boxster (one of the most agile cars on the planet) did 58mph in the same test.

IMHO, the GL is fine and my truck is scheduled for delivery to the dealer this week.

I don't expect a 5000lb vehicle to perform like a mid-engined sports car (something about physics) and ~13mph is a small spread. I'd rather hit something under control with the benefit of crumple zones and air bags than roll multiple times into other potential unmovable objects.

http://consumerreports.org/cro/2012/...ance/index.htm

 

I was surprised by this test video. I have the X166 550 and it doesn't do this -- what it does do -- anywhere from 35 to 50+ mph is delay response to the throttle, not lock up the "outside" front to force the car ahead. The intervention of the stability control system is horrible, but it doesn't do this anti-roll-over nonsense in the 550, it just cuts the throttle (down or off, in any case, it halts forward acceleration from the engine.) And it's all the stability control intervention, because if you turn off the squiggly lines under the car button, the handling is perfect. In fact, the handling is neutral and near perfect with stability control activated, so long as you stay within its absurdly quirky envelope of what it considers plausible vehicle dynamics and control inputs.
I find that in Sport mode (when the active systems use the damper pressure and I think some active anti-roll bar pre-load) the body roll is negated. It does have a "you're going too far" mode where it starts to let the body roll over once it has reached some limit, but in general, without absurd steering input, you can maintain a much (much) higher apex speed without the car or passengers complaining at all. But be prepared for a firm, but not quite jostling ride.
I think MB needs to completely rethink their stability control in the X166. I don't recall any of this grief in the X164 and we drove with similar "alacrity" and I have over two decades of race experience as amateur with some lap records to my credit, so I'm not entirely without a reasonably mature opinion.
Compared to other Mercedes and a Cayenne Turbo S, the GL is a sublime handling SUV -- it is neutral and communicative at its limits. It does tend to work the front tires on the outside shoulder, but no surprise with the twin turbo V8 and transmission all wanting to escape through the straightest line exist at each tun. Still, with a balanced and progressive throttle, the 550 will set on its suspension, load up the rear and rotate correctly on a steady steering angle. The Cayenne needs exhausting finesse to coax it into this kind of transition, but the GL will find its way there and show you the way if you're a bit early or a bit late or a bit quick or slow. The BMW X5M can do a similar job, but it's a much smaller, shorter vehicle and very much compromised in ride comfort to keep it on its toes. The active handling of the GL is to be applauded. The stability control, well, it stays on, but I do turn it off for my own preference when I know it's going to be annoying and not helpful (such as the five miles of winding mountain road up to our house when I want to maintain a steady clip.)
I'd suggest everyone find a safe stretch of road off the public roads, say an old factory side road, and practice a comfortable left-right-left swerve avoidance, build up speed with confidence, have wide open run-off areas, then put down some cones and see how the car fares. First suggestion is add 5-10psi to the tires to the max load plate specification (remember cold pressure.) In my experience in the 550 with active controls, if you ease the throttle (which "tells" the computers you're not out of your depth) before/during the swerve, rather than a hasty life-off/swerve/panic brake (which will induce brake assist) you'll get a clean, controlled S path swerve around the obstacle.
Safety-conscious drivers should learn to drive, then practice driving in all conditions before encountering those conditions in an unplanned situation. I see this all too often where I live (mountain roads, snow, windfall debris ... things that a driver should have no trouble negotiating) and all too often I see a conscientious driver in an old 2WD car breeze through, then someone, let's say "not on the ball" will come blundering along ... mix in a little bad luck and you're in the ditch, or worse.
All that said, I'm on my third GL, approaching 100K miles, driven in extremely adverse conditions from sand to mud and blizzard mountain passes with 16 percent grades on metal studded snow tires and chains ... never a single fault or failure. This reminds me of the day we were literally blown sideways off the road onto the soft shoulder at about 30 mph by an unprecedented gust (in a valley) and the pre-tension of the seat-belts came on! I made a very light steering adjustment (coasting, almost zero throttle angle) and old girl just righted her course and we stayed out of the bank. I can't say my heart rate didn't "spontaneously increase my vigilance" but in that case, the stability system did it's job proudly and saved my bacon (no amount of car control short of being a rally car driver and taking risk between your gritted teeth can control a car when all four wheels are turning, slipping and drifting at once ... efforts to "catch it" usually only amplify the outcome adversely ... hence the strictly enforced rule in racing such as NASCAR or any banked circuit type racing, that any degree of slip and the driver is required to go "both feet in" ... meaning fully apply the brakes and fully release the clutch to allow the engine to keep running ... no margin for error, no consideration given to a skilled, professional driver being able to "catch it" ... so as a rule, by all means, lift off, but generally don't try to "turn into the slide" ... in modern systems, steer for your best outcome exit and resist the temptation of "negative outcome fixation" ... meaning "don't stare at the tree you're trying to avoid, instead, fix your attention on the path to a safe continuation without getting to know the insurance details of other drivers" ... : )
Bottom line, the appearance of the CR test is misleading, but that doesn't turn a blind eye to the flaws in the MB stability control.