What should I do? on 1991 Volvo 240

whats wrong when you press on the brakes and the steering wheel shakes?

Asked by for the 1991 Volvo 240
This is because there is likely a problem with your front brake rotors. On the 240 you will need to replace the pads and rotors, and have the wheel bearing hub assemblies checked to make sure they are OK before installing new pads and rotors.
Here is some more info about brake vibrations: