when driving freeway cars jumps side to side when steering
Sounds like some loose front end parts. Need to get it in and have it checked, its pretty bad if it is doing that. Check asap.
Can be worn tie rod bushing, control arm bushing, ball joint, alignment, even a bad tire... if you're not able to diagnose/fix, get it into a shop. A quick test you can do yourself is jack the car up, and push/pull on the tire at the top, and on the front of the tire. Any play? Don't be shy about grabbing that tire and push/pull hard, either.
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