Symptom Chart: NVH

WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

Condition	Possible Sources	Actions
Axle howling or whine	Axle lubricant low	CHECK the lubricant level. FILL the axle to specification. REFER to: Differential Fluid Level Check .
	Axle housing damage	INSPECT and INSTALL a new axle assembly as necessary. REFER to: Axle Assembly .
	Damaged, worn or incorrect ring and pinion gear contact	INSPECT and INSTALL a new ring and pinion set as necessary. Refer to, Contact Pattern of this procedure, or REFER to: Drive Pinion .
Driveline clunk - loud clunk when shifting from REVERSE to DRIVE	Incorrect axle lubricant level	CHECK the lubricant level. FILL the axle to specification. REFER to: Differential Fluid Level Check .
	Excessive backlash in the axle	CHECK for excessive axle backlash. ADJUST backlash as necessary. REFER to: Ring Gear Backlash Adjustment .
Driveline clunk -- occurs as the vehicle starts to move forward following a stop	Pinion gears	CHECK and REPLACE as necessary REFER to: Differential Carrier .
Grinding, popping or chattering - noise from the rear axle when the vehicle is turning	Damaged or worn differential (differential side gears and pinion gears)	INSPECT the differential carrier and the components of the differential carrier. INSTALL a new differential carrier and/or differential carrier components as necessary. REFER to: Differential Carrier .
High pitched chattering -- noise from the axle when the vehicle is turning	Incorrect or contaminated lubricant	CHECK the vehicle by driving in tight circles (5 clockwise, 5 counterclockwise). CLEAN and REFILL the axle to specification. REFER to: Specifications .
	Damaged or worn differential (differential side gears and pinion gears)	REPAIR or INSTALL new differential side gears or pinion gears as necessary. REFER to: Differential Carrier .
Grunting -- normally associated with a shudder experienced during acceleration from a complete stop	Loose rear axle mount bolts or suspension fasteners	CHECK for loose bolts. TIGHTEN to specifications. REFER to: Axle Assembly .
Howl - can occur at various speeds and driving conditions. Affected by acceleration and deceleration	Incorrect ring and pinion contact, incorrect bearing preload or gear damage	INSPECT and ADJUST as necessary. Refer to, Contact Pattern of this procedure, or REFER to: Differential Carrier . REFER to: Ring Gear Backlash Adjustment .
Chuckle - heard at coast/ deceleration. Also described as knock	Incorrect ring and pinion contact or damaged teeth on the coast side of the ring and pinion	INSPECT and INSTALL a new ring and pinion set as necessary. Refer to, Contact Pattern of this procedure, or REFER to: Drive Pinion .
Knock - noise occurs at various speeds. Not affected by acceleration or deceleration	Gear tooth damage to the driver side of the ring and pinion	INSPECT and INSTALL a new ring and pinion as necessary. REFER to: Drive Pinion . REFER to: Differential Carrier .
Scraping noise - a continuous low pitched noise starting at low speed	Worn or damaged pinion bearings	INSPECT and INSTALL new pinion bearings as necessary. REFER to: Drive Pinion .
Driveline shudder - occurs during acceleration from a slow speed or stop	Rear drive axle assembly mispositioned	CHECK the axle mounts and the rear suspension for damage or wear. Repair as necessary. REFER to: Axle Assembly .
	Loose rear axle bolts	CHECK the rear axle for loose bolts. TIGHTEN the bolts as necessary. REFER to: Axle Assembly .
	Driveline angles out of specification	CHECK for correct driveline angles. REFER to: Driveshaft Angle Measurement .