Three problems related to driveshaft have been reported for the 1997 Ford Expedition. The most recently reported issues are listed below.
The rear lower trailing arms that hold the rear axle in place are made too thin and with corrosion will fail. This will cause the rear axle to move backward and break the drive shaft.
When I get up to 50 mph, the vehicle starts to vibrate. I have had nothing but problems with the vehicle since I bought it. I took it to two different Ford dealerships and they could never find out what the problem was. By me spending thousands of dollars trying to get other things fixed which wasn't even the problem, I now find out that it is the transfer case, which is about $1300 just for the part. I will never buy a Ford again.
Vibration in drive train, very noticeable at highway speeds when foot is removed from accelerator.