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Understeer

exactly what is understeer? Will Mercedes have “understeer”?

Understeer is when the vehicle doesn’t turn in the direction the driver intends. Instead the front tires slide to the outside of the curve before the rear tires lose traction.

Understeer can occur with any vehicle if the curve is taken too fast for the traction capabilities of the tires.

Tester

FWD cars, or any car with uneven weight distribution (60-40 front/rear) tend to understeer, also called “push”. The opposite problem, oversteer, is when the rear wheels lose traction first and the rear end slides out…RWD Benz cars tend to have neutral steering response. In normal driving, you will never encounter either.

Generally speaking, a car with its engine in the front will have a tendency to understeer, and the effect is more pronounced if the car has a particularly heavy engine. What this means is that the car does not react to your steering input as much as you might want in a high speed maneuver, with the result that it tends to “plow” straight ahead, rather than turn as you want it to.

By contrast, a rear-engined car will have a natural tendency to oversteer, and this effect is more pronounced if the engine is mounted very far to the rear and if the engine is heavy. What this means is that, in a high speed turn, the rear end of the car will attempt to become the front end of the car.

All of this being said, intelligent suspension design can ameliorate much of this problem, and modern cars are not as prone to these phenomena as older cars were.

Others have explained understeer. Most passenger cars are designed, for safety reasons, with a slight tendency to understeer if pushed to the extreme limits of their handling.

This is to prevent the vehicle from spinning.

Mercedes Benz uses a very sophisticated suspension and steering system. It is unlikely that you will ever push a Mercedes Benz hard enough to experience understeer. Most people never experience it, even in cars with much more of a tendency to exhibit understeer than a Mercedes will have.

Thanks to everyone for the explanation of understeer. I never experienced it my Mercedes nor my Cadillac Catera. But, this Acura gives me fit at 75mph on many interstate curves.

Thanks Again.

You’ve found out one reason why Acura hasn’t been able to fully compete with BMW and Mercedes - they’ve stuck with FWD on several models, to the detriment of handling. The latest TL is available with AWD to improve the handling, but it’s still not as good as the other RWD competitors. A good value? Yes, but not the best handling cars out there.

Auto manufacturers have designed “understeer” into their cars because most drivers can handle an understeering car. Most drivers will be unable to control an “oversteering” car. When an “understeering” car tries to turn too fast, the front “plows” to the outside of the turn and is unlikely to spin. You will be going ‘off road’ but you are going straight ahead. But with an “oversteering” car like a Corvair the rear end tracks outward on the turn and the front wheels have to be counter steered to maintain the correct slip angle on the front tires. If the front wheels are held steady the slip angle soon becomes so steep that the front and back tires are soon sliding sideways. If the tires hit a curb or go off the road the car can easily roll over. The reason Nader was death on the Corvair was that regular drivers could not recognize and correct for “oversteer” conditions. Many a VW beatle met its demise when grandma took a corner too quickly. I once saw a law suit brought by a woman who off roaded a Posche Carrera because Porsche built a car so fast and unstable that she could not handle it, LOL.

I regularly drive my FWD Acura around interstate curves at 75 mph, and it does NOT understeer. I’d have someome look at the alignment. If that’s OK maybe better tires are in order. These are not the conditions under which you should be able to feel understeer. You should have to push it much harder than that to feel it.

TIRES can play a MAJOR roll in this…Try increasing the pressure in the front tires by 5-6 psi and see how that feels…