GM Austin:
Atzporsche:

How did they manage such a shitty behavior.. the chassis is from Mercedes and their car has no such issues.

The design objective is different. As I said previously, a good off-road suspension is a horrible on-road performer.  Jeep advertises that all their vehicles are Rubicon tested, or something like that.  Meaning their vehicles can navigate the Rubicon Trail, or any other similarly rugged terrain. High ground clearance is one thing that is required, which will give the vehicle a higher center of gravity (not desireable for on-road).  The next thing is wheel articulation.  In order to maintain contact with the ground when the ground is very uneven the wheels need the freedom to move very independently from one another from left to right so that you can maintain traction. If you are climbing a hill and the left wheel has to go over a large rock, you don't want the right wheel to come off the ground because of that.  You want the right wheel to maintain contact with the ground so you don't lose traction and the vehicle slide backward.  This means the anti-roll bar needs to be smaller in diameter than what would normally be recommended for good on-road performance.  The off-road desireable feature of the left and right wheels having good independent verticle movement is exactly counterproductive to good on-road performance, as we see in the video.  Severe body lean when cornering is a fact of life for the off-road tuned suspension. Correcting the bad on-road manners will compromise the off-road ability.  Jeeps and Land Rovers are both good off-road performers and both suffer from serious body lean when cornering at speed. If they take a model and alter it for good performance on the pavement (a Range Rover model comes to mind), one of the things they will do is increase the roll-bar diameter, reducing body lean when cornering, but also reducing the left/right independent whell movement and compromising the off-road ability. 

Modern Landies tackle these issues with the use of adjustable suspension. Still, they are no Cayenne or X5 competitors on the road, but their off road credentials are second to none.


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FERRARI RULES!!!