Thats a good diagnosis.
I looked up the problem on the NHSTA site. There appears to be no milage or time limit. It looks like Ford will have to fix this problem, I hope.
Here is the recall.
NHTSA Recall No. 98V323/Ford Recall No. 98S36
Vehicles: Ford 1986-1995 Ford Taurus and Mercury Sable vehicles manufactured from October 14, 1985, through June 27, 1995; and certain 1988-1994 Lincoln Continental vehicles manufactured from November 4, 1987 through November 18, 1994.
Population: 2,697,000 vehicles sold or currently registered in the states of Connecticut, Delaware, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Vermont, Virginia, West Virginia, Wisconsin, and the District of Columbia.
Problem: The rear lower sub frame mount plate nut can experience stress corrosion cracking if subjected to long-term exposure to road salts which are used extensively in the above listed states. Detachment of the body mounts at the rear corners of the sub frame, which supports the engine and transmission, would allow the rear corners of the sub frame to drop. If both rear corners of the sub frame drop, steering could become suddenly very difficult, adversely affecting vehicle control and possibly result in a crash.
Remedy: Dealers will install sub frame rear mount bolts, reinforcement plates, and plate nuts. Owners should contact Ford at 1-866-436-7332.