One problem related to front suspension has been reported for the 1998 Toyota Tacoma. The most recently reported issues are listed below.
At speeds over 45, front end vibrates badly and is hard to control. I have replaced the tires which worked until the tires had 5000 miles of them, balanced tires, and had front end alignments. The Toyota dealership is aware of the problem, but cannot come up with a solution to correct the problem. I know of other Tacoma owners with similar problems. ( dot number: tire size: 31x10. 5 15 ).