Our vehicles are full of reciprocating, rotating parts that have to fall within certain measurements, or tolerances, in order to perform properly.
If an axle gets bent — which is actually quite easy to do in a collision or other mishap — it will create a jostle of a ride afterward. With this problem, the vibrating often picks up in intensity the faster you drive.
A related problem would be that the driveshaft also needs inspection. This rapidly spinning part transfers engine power to the rear axles and wheels in rear-wheel drive vehicles. If it's bent, it can cause shaking.
Worn-out constant velocity (CV) joints fall under the same category. If the "boots" — those rubber, accordion-like coverings around the ends of the drive axles — are intact, clamps are secure and no lubricant is seeping out, chances are they're not the problem. But if the boots are torn, that means dirt and dust and road filth are getting in and damaging the joints. For front-wheel drive cars, toasted CV joints mean you'll be buying new drive axles, too.