Some 2011 Mustang vehicles equipped with a 3.7L engine and have an engine build date on or before 2/11/2011 may exhibit a squeal noise from the accessory drive belt during a cold engine start. The concern may be worse during cold and damp weather.
Follow Service Procedure to correct this condition.
If accessory drive belt squeal occurs all the time, engine cold or hot, do not continue with this article. Perform normal diagnostics. Refer to Workshop Manual (WSM), Section 303-05.
Determine the engine build date. Refer to WSM, Section 303-01A.
If engine build date is on or before 8/16/2010, replace coolant pump pulley and accessory drive belt with appropriate revised service parts. Refer to WSM, Sections 303-03 and 303-05.
If engine build date is 8/17/2010 - 2/11/2011, replace accessory drive belt with appropriate revised service part. Refer to WSM, Section 303-05.
If engine build date is on or after 2/12/2011, do not continue with this article and perform normal diagnostics. Refer to WSM, Section 303-05.
Coolant Pump Pulley
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage IMPORTANT: Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.
2011 Mustang 3.7L: Check Engine Build Date, And Replace The Accessory Drive Belt (Do Not Use With Any Other Labor Operations)
2011 Mustang 3.7L: Check Engine Build Date, Replace The Coolant Pump Pulley, And Accessory Drive Belt (Do Not Use With Any Other Labor Operations)