One problem related to engine oil leaking has been reported for the 1998 Jeep Wrangler. The most recently reported issues are listed below.
Engine had a clatter noise and short block was replaced. Ever since, there has been excessive vibration whenever vehicle is running - does not have to be moving. Previous engine did not have vibration. Other vehicles test driven to compare do not vibrate as strongly. Dealer states this is a normal vibration and will not do anything about it. Rear axle housing had oil leak due to axle tube not seated properly into center housing. Complete rear axle assembly was replaced. No problems with this.