It is most likely one of three things...
1 broken strut spring
2 worn out sway bar bushing
3 loose muffler
When you turn the wheel, or while you drive?
worn suspension (ie), ball joints , tie rod ends also possibly cv joint wear but most likely ball joints worn your answer here...
why is my '99 ford taurus making a knock noise and smoking from under the radator
The cause of the clunking is probably the sway bar link. They are made of white platic and eventually wear out. Both sides were shot on my 2001 Taurus at 75,000 miles. It is a job you can do your self if you are handy with tools. The parts are About $28.00 per side at your local auto parts store and about $38.00 each at the Ford Dealer.
probably a blown head gasket
Check for loose/worn steering components i.e. tie rod ends, ball joints
cv joint damage.repack or change it. repacking may do to solve your problem
sounds like the right front motor mount .i replaced mine and the clunking sound went away
it might be your starter.
The Ford Taurus does not have a timing belt, it has a timing chain. The timing chain is designed to last the life of the engine, and does not need routine replacement.
link pin needs replace
Check the lug nuts immediately. Check tha clip that holds the brake pad on. I had a loose pad that made more of a tick sound that went away when I pressed on the brakes