Two problems related to side/rear glass have been reported for the 1998 Volkswagen Passat. The most recently reported issues are listed below.
Locking pin failed causing the left rear window to come off it's track. Nlm.
The right front seats would rock whenever vehicle is turning corners or curbs. This also happens when coming to or leaving a stop sign or light. Contacted manufacturer & nothing could be or would be done. Sun roof would open & close on its own. Would have no warning. The rear window looked like it had acid rain on it when bought. Been to dealer & mechanic removed seat & replaced it. No problem found. Checking on other problems.