Symptom Chart -- NVH
WARNING: This page is about a different car, the 2020 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
NVH symptoms should be identified using the diagnostic tools that are available. For a list of these tools, an explanation of their uses and a glossary of common terms, refer to NOISE, VIBRATION AND HARSHNESS
. Since it is possible any one of multiple systems may be the cause of a symptom, it may be necessary to use a process of elimination type of diagnostic approach to pinpoint the responsible system.
Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods .
| Symptom | Possible Sources | Action |
|---|---|---|
| Grinding / clicking / ratcheting noise from front axle in 2H mode under acceleration or heavy loads | Vacuum leaks Vacuum check valve |
Refer to PINPOINT TEST J : THE FRONT AXLE MAKES GRINDING / CLICKING / RATCHETING IN 2H MODE ONLY |
| The front axle makes noise in 2H mode only and generally under heavy throttle | Vacuum leaks Vacuum check valve Vacuum reservoir IWE solenoid IWE s |
Refer to PINPOINT TEST J : THE FRONT AXLE MAKES GRINDING / CLICKING / RATCHETING IN 2H MODE ONLY |
| The transfer case makes noise | Tire inflation pressure Tire and wheel size Tire tread wear Internal components Fluid level |
MAKE SURE that all tires and wheels are the same size and that the inflation pressures are correct. CHECK tire tread wear to see if there is more than 1.6 mm (0.062 in) or 2/32 inch difference in tread wear between front and rear. INTERCHANGE one front wheel and one rear wheel. ROAD TEST again. OPERATE the vehicle in all transmission gears. If there is noise in the transmission in NEUTRAL, or in some gears and not in others, REMOVE and REPAIR the transmission. REFER to: Diagnosis By Symptom . If there is noise in all gears, DISASSEMBLE the transfer case. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case . CHECK the planetary gears, the bearings, the upper and lower drive sprockets and drive chain for damage. INSTALL new parts as necessary FILL with automatic transmission fluid. |
| Transfer case whine -- noise at all ranges | Incorrect fluid level or fluid quality Worn oil pump Under-inflated or oversized tires |
CHECK that the transfer case is filled to the correct level and with the specified fluid. REFER to: Transfer Case Draining and Filling
. DISASSEMBLE the transfer case. CHECK the oil pump for wear or damage. REPAIR as necessary. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case . CONFIRM that the tires and wheels are correct for the vehicle. CHECK that the tire inflation pressures are correct. |
| Transfer case growl/rumble -- noise at all ranges | Damaged or worn bearings or planetary gear | DISASSEMBLE the transfer case. CHECK the bearings or planetary gear for wear or damage. REPAIR as necessary. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case . |
| Transfer case scraping/grating -- noise at all ranges | Excessively stretched drive chain hitting the case | DISASSEMBLE the transfer case. CHECK the drive chain for wear or damage. REPAIR as necessary. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case . |
| Transfer case howl/hum -- noise at all ranges or 4H only | Worn or damaged sun (input) gear, clutch pack (intermediate) gear or output shaft gear | DISASSEMBLE the transfer case. CHECK the gears for wear or damage. REPAIR as necessary. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case . |