Driveway Pinpoint Test
Park on flat ground, engine off. Reach through the wheel spokes and run a finger across the rotor face β you should feel smooth metal. If you feel grooves deep enough to catch a fingernail, or the rotor looks scored with concentric rings, that confirms rotor wear. Also note: does the shaking come mostly through the steering wheel (front rotors) or through the seat and floor (rear rotors)?
Fix-vs-Skip Money Panel
DIY Cost
~$80
parts only
Shop Cost
~$300
parts + labor
If you skip it
Continuing to drive on warped rotors extends pad contact time and glazes the pads. Within 5,000β10,000 miles you'll lose significant braking power; a full brake system failure (rotor cracking, caliper damage) can turn a $300 job into a $900 repair.