If it does it when you are applying the brake, it is a sign that you need to have your brakes serviced (sounds like a warped rotor or a failed ABS sensor). Otherwise you should have your alignment checked and tires rotated.
Most probably
I would suspect a bent wheel, but it can also be a tire out of balance, loose lug nuts, bad wheel bearing, or worn steering or suspension parts.
Most likely bad tire or a wheel bent, or out of balance
Yes it is just very hard to turn the wheel when you slow down
They stop your car. They are round discs that are kind of attached to the wheels and the pads grip the rotors when you apply the brakes to slow down the car. When a rotor becomes warped due to excessive heat, the steering wheel will shake when you apply the brakes.
Replace your steering dampner. Mine did the same thing.
The steering wheel shimmering could be warped front rotors, when slowing down. The stalling when slowing down could be a bad fuel filter.
turning the steering wheel uses pressure from the power steering pump and puts a load on the engine causing it to slow the rpm. Should rise again when you stop turning the wheel. completely normal.
Warped rotor,Tie rods, Wheel bearings (hub).
Your vehicle is.. off does not have electrically assisted steering is broken
If the car is only shaking when you are applying the brakes, the most likely reason is warped rotors. The rotors can become warped when they are overheated and then cooled off too rapidly. This can happen when you have hot rotors and then you run over a puddle and the water splashes on them.
One way to fix a slow steering return on a Mercedes SLK 350 is to add more power steering fluid. Another option is to replace the steering wheel lock sensor.