If a noise from the rear end is heard when going around turns or after driving at highway speed for an extended period, this could be caused by a failing deferential clutch kit. An updated differential clutch kit available.
1990 Ford F-150 Problem Reports
Newest 1990 Ford F-150 Problem Reports
If there is a vibration or noise at highway speed, it could be from the frontdrive shaft and may require replacement of the double cardan joint. A double cardan joint is a type of driveshaft joint that uses two universal joints.
The engine oil pan gasket can develop a leak. Leaking oil may accumulate on the exhaust system resulting in a burning smell. Replacing the gasket should correct this leak.
The battery light may illuminate on the instrument panel because the alternator wire harness connector is damaged. A new connector kit is available and should be installed to correct this concern.
Heater Blower runs only at low even when selector is on high
unpluged the blower ran direct off battery and it ran at full speed
Tubes for the EGR system (exhaust gas recirculation) can break, causing an exhaust leak and noise under the hood.