Symptom Chart - NOISE, VIBRATION & HARSHNESS (NVH)

WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: NOISE, VIBRATION & HARSHNESS (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 & HARSHNESS article. 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. If this is not the causal system for the symptom, refer back to NOISE, VIBRATION & HARSHNESS article for the next likely system and continue diagnosis.

Condition	Possible Sources	Action
Vibration when the brakes are applied	Tires	CORRECT any wheel and tire concern before diagnosing the brake or suspension systems. REFER to WHEELS & TIRES article to diagnose the tires.
	Uneven brake pad wear Brake disc pad transfer Uneven brake disc wear Suspension components	COMPLETE the brake system inspection described in Inspection and Verification - Hydraulic Brake System e. If the condition still exists, go to Pinpoint Test B .
Brake vibration/shudder - occurs when the brake pedal is released	Brake caliper guide pins	INSPECT the brake caliper guide pins for correct operation. REFER to Brake Caliper Guide Pins .
	Brake drag	Go to Symptom Chart - Brake System .
Rattling noise	Caliper mounting bolts loose	CHECK the caliper bolts. TIGHTEN to specifications. REFER to FRONT DISC BRAKE article for front disc brakes or REAR DISC BRAKE article for rear disc brakes.
	Damaged or worn caliper guide pins or retainers	CHECK the caliper guide pins and retainers for correct operation. REFER to Brake Caliper Guide Pins . INSTALL new components as necessary.
	Missing or damaged anti-rattle clips or springs	CHECK the brake pads for missing clips or broken springs. INSTALL new components as necessary. REFER to FRONT DISC BRAKE article for front disc brakes or REAR DISC BRAKE article for rear disc brakes.
	Loose brake disc shield	TIGHTEN the brake disc shield bolts to specification. REFER to FRONT DISC BRAKE article for front disc brakes or REAR DISC BRAKE article for rear disc brakes.
Clicking noise - with brakes applied with ABS brakes	ABS hydraulic control unit	Acceptable condition during an ABS event.
Squealing noise - occurs on first (morning) brake application	Brake pads	Acceptable condition. Caused by humidity and low brake pad temperature.
Squealing noise - a continuous squeal	Brake pads worn below minimum thickness	INSPECT brake pads for excessive wear, taper wear or uneven wear. VERIFY brake pads are within minimum specifications. REFER to Brake Pads .
Squealing noise - an intermittent squeal brought on by cold, heat, water, mud or snow	Brake pads	Acceptable condition.
Groaning noise - occurs at low speeds with brake lightly applied (creeping)	Brake pads	Acceptable condition.
Grinding noise - continuous	Brake pads worn below minimum thickness	INSPECT the brake pads, brake discs, and attaching hardware for damage. VERIFY brake components are within specifications. REFER to SPECIFICATIONS .
Moaning noise	Brake pads contaminated with grease or oil	INSPECT the brake pads for contamination. REPAIR or INSTALL new components as necessary. REFER to FRONT DISC BRAKE article for front disc brakes or REAR DISC BRAKE article for rear disc brakes.