Symptom Chart: NVH

WARNING: This page is about a different car, the 2023 Lincoln Nautilus. However, it is still accessible from the selected car via links, so may be relevant.

Symptom Chart

Condition	Possible Sources	Actions
Driveline clunk - loud clunk when shifting from REVERSE to DRIVE	Damaged or worn CV-joints	INSPECT the CV-joints for wear or damage. INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
	Damaged driveshaft center bearing support	INSPECT the insulator for wear or damage. INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
Driveline clunk -- occurs as the vehicle starts to move forward following a stop	Worn driveshaft CV-joint with excessive play	INSPECT the CV-joint for a worn condition. INSTALL a new driveshaft if necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
	Damaged driveshaft center bearing support	INSPECT the insulator for wear or damage. INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
Buzz - buzzing noise is the same at cruise or coast/deceleration	Incorrect driveline angles	CHECK for correct driveline angles. REPAIR as necessary. REFER to: Driveshaft Angle Measurement .
Rumble or Boom - noise occurs at coast/ deceleration, usually driveshaft speed-related and noticeable over a wide range of speeds	Driveshaft out of balance	CHECK the driveshaft for damage, missing weights or undercoating. REFER to: Driveshaft Runout and Balancing . INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
Grunting -- normally associated with a shudder experienced during acceleration from a complete stop	Driveshaft CV-joint binding	INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
Driveline shudder - occurs during acceleration from a slow speed or stop	Driveline angles out of specification	CHECK for correct driveline angles. REFER to: Driveshaft Angle Measurement .
	Binding or damaged driveshaft CV-joint	INSPECT the driveshaft CV-joints and coupling shaft for wear or damage. INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
Driveline vibration - occurs at cruising speeds	Worn or damaged driveshaft center bearing support	CHECK the insulator for damage or wear. ROTATE the driveshaft and CHECK for rough operation. INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
	Loose axle pinion flange bolts	INSPECT the axle pinion flange. TIGHTEN the pinion flange bolts to specification. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
	Excessive axle pinion flange runout	CARRY OUT a runout check. REPAIR as necessary. REFER to: Specifications .
	Driveshaft is out of balance	CHECK the driveshaft for damage, missing balance weights or undercoating. CHECK the driveshaft balance. CARRY OUT a driveline vibration test. REFER to: Driveshaft Runout and Balancing .
	Binding or damaged driveshaft CV-joint	INSPECT the driveshaft CV-joint for wear or damage. INSTALL a new driveshaft as necessary. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .
	Excessive driveshaft runout	CARRY OUT a runout check. REFER to: Driveshaft Runout and Balancing .
	Driveline angles out of specification	CHECK for correct driveline angles. REPAIR as necessary. REFER to: Driveshaft Angle Measurement .
	Center bearing bolts not properly seated	REPLACE and TORQUE the center bearing bolts. REFER to: Rear Driveshaft - 2.0L EcoBoost (184kW/250PS) - MI4 . REFER to: Rear Driveshaft - 2.7L EcoBoost (238kW/324PS) .