2009 Sonata with front tires jacked up off the ground and only right tire seems to rotate when I put it in drive and press on accelerator. Left barely moves at all.

jack up front left on level ground ,support and chock rear wheels and set park brake ---look and check the cv axle for leaks,tears or damage -put in neutral and watch axle should turn smoothly turn steering wheel to left and rotate tire again watching axle if their is binding or grinding or studder movement than axle is damaged and needs to be replaced

Hi i would check the rotation of the tyres, (IE) TAKE the right hand rear wheel and put that on the left hand front, and do the same with the other one , also check that you have no flat spots on the tyres from hard breaking and the vehicle standing for a period of time can cause this to happen,also its not to hard to repack your bearings with grease, to see if that is the problem, and remember oil and grease are a lot cheaper than parts, good luck and safe driving

If its not the bearing and your Mercury is front wheel drive, it could be the "CV" joints.
It could be both....

Is the wheel rubbing the brake caliper?

Is something like the wheel well liner rubbing the tire(airflow pushing it into tire)?

Jack the tire off the ground and rotate it by hand. Push in & out at the top, sides, and bottom of the tire. Little or no play is considered acceptable. If you get a "clunking" sound and/or a lot of play the bearing(s) are bad. (If front wheel drive, chock rear tires, put transmission in neutral so you can rotate tire.)

Hope this helps.

Verify tire pressures, and tires with the same amount of time on the ground. Rotate front to back, diagnostically. Also, a brake failing to release can cause a similar symptom.

you lift the car up on jacks so that the tires are off the ground, then you put jack stands in placement. then you loosen ONLY THE BOLTS ON THE TIRE IN THE AIR remove the tire let the car down on to the jack stands, and move the jack to the next and do the same what you do is take the passenger side back tire and switch it with the drivers side front tire. then you take the drivers side back tire and switch it with the passenger side front tire. make sure the bolts are tight as you can get them then you are done. i hope this information helps. Be careful and drive safe!

Sounds like a bad cv joint. Easy way to check is to raise the front of the vehicle so both front tires are off the ground. Use jack stands under the vehicle and block the rear tires. Start the engine and put the tranny in drive. Let the front wheels rotate while the engine is idling and turn the steering wheel slowly in both directions. Listen for the clunking noise. You may have to speed the engine up a little to make it work.

does the vibration stop when not under load, (coasting) Possible front axle shaft or hub bearing. hows the tire condition,no shifted belts or odd shape? notice balance weights missing? Is this a auto or manual, If manual do you feel more vibe in pedal or wheel? Jack front of car, assuming front wheel drive? Brace care with jack stands, block rear wheels, put car in nuetral, rotate front tires in both directions,each side, and listen,feel, look at all moving parts. also move tires in and out at the nine and three o clock position,(as if the tire was turning right and left) help is great while doing this as it allows you to be under car and visually inspect steering components,tie rod ends and inners. grab tire at six and twelve o clock and try to wiggle back and forth, grab a 2x4 and put under each tire and have helper pry up and down. you will be checking for upper ball joint slop. this should give you a good idea of what the problem is. Hows the motor mounts?

Start by driving the car very slow down a flat road. If the sterring wheel wobbles back and forth do this. If you know which side has the worst shimmy jack the front wheels off the ground so you can rotate each tire freely. Have another person with you for four eyes are better than two for this proceedure. One will rote each front tire slowly looking for a buldge in the tire. If you do see a buldge in the side wall or on the tread area which sticks out that is cqaused by a broken belt in the tire. That will cause a shimmy as you drive.

Jack up the front end and put stands under it and block rear wheels. Look at axle boots and see if they are cracked. Try turning wheel back and forth sharply and see if you can hear any clicking. Problem could be outer axle joints. If the boots are cracked or you hear a clicking noise you will have to replace the axle. The axle and boot come as a complete unit. Please let me know what you find out.

first i would check the tires , are they cupped or chopped on the tread? run your hand over the tread and see if it feels rough and uneven. take the truck to a auto repair shop and have them jack both front and rear axles off the ground, put the truck in 2 wheel drive and run the speedometer to the speed you usually hear the roaring noise, if you don't hear the noise , put the truck in 4 wheel drive, turn off the traction assist if it has one and run it to the speed you would hear the noise. if you hear the roaring noise with tires off the ground, the problem is in the drivetrain, (engine, transmission, transfer case, u-joints, differentials or the front left or right cv halfshafts or u-joints). the older models (97 98) had the front two driveshafts from the differential turning all the time, they engaged in 4 wheel drive from the transfer case and a solenoid on the front differential. depending on the miles you have on this truck, the most likely areas i would look at would be the tires, u-joints/cv joints, and front and rear wheel bearings. thanks and good luck.