Why is my steering-wheel wobbly and seat at low speeds

Check for worn steering components. IE. worn tie rod ends, worn steering gear box.

check the tire pressure on all four wheels to make sure they are correctly inflated.

rebalance the tires

Improperly balanced wheels can cause the wheels to wobble at speed which can be felt through the steering wheel. A local tyre shop can test the wheels for balance and make the necessary adjustments to the wheels by adding weights to even out the balance.

Defective rack and pinion steering gear.

Go to an Alignment Only Shop & have them road test
while you ride along

Then have them inspect for worn parts

Does this wobble the steering wheel or your seat? The difference is very important. If it shakes the steering wheel, you have warped front rotors. If it's more through the car and seats, rear rotors are warped. Let me know please.

Does your steering wheel wobble at parking lot speeds, or your ****. If either, you have a bad tire, have it checked ASAP. (if steering wheel wobbles its a front tire.)

U NEED TO HAVE THE CV JOINTS CHECKED FOR EXCESSIVE WEAR, ALSO ROTATE THE TIRES AND SEE IF THAT HELPS, A SEPERATED TIRE CORD CAN CAUSE THIS WALLOW.

This happened to my Buick. The front tires had little facets worn on them, causing the trembles. Yours sounds even more severe. But for my car, I adjusted the toe in and rotated the front tires to the back. The steering wheel doesn't tremble any more. But there is a rumble in the seat. I can live with that. Bad shocks. Bad alignment. These cause the facets.