2006 FORD MUSTANG

Typical onset: 80,000-130,000 mi

Symptoms: Harsh 2-3 or 3-4 shifts, especially when cold, Slipping under acceleration, flaring between gears, Whining or grinding noises from bellhousing, Check engine light with P0733, P0732, P0734 codes

Fix: The 5R55S is known for intermediate clutch pack failure and valve body issues. Rebuild takes 8-12 hours; remanufactured units are often more cost-effective. Many shops won't warranty a rebuild on high-mileage units. Cooler lines and radiator-mounted cooler also fail, causing contamination.

Estimated cost: $2,800-4,500

Typical onset: 60,000-100,000 mi

Symptoms: Loud pop or bang from engine bay, sudden misfire, Hissing sound from cylinder head, loss of compression on one cylinder, Check engine light with cylinder-specific misfire codes, Spark plug shoots out of head under load

Fix: The 3-valve 4.6L has notoriously weak spark plug threads. Plugs can break on removal or blow out entirely. Thread repair requires special TimeSert or HeliCoil inserts (2-3 hours per hole if head stays on). If multiple threads strip, head removal and machine work required (12-16 hours). Prevention: replace plugs every 30k with anti-seize and proper torque.

Estimated cost: $600-1,200 per cylinder, $3,500+ if head removal needed

Typical onset: 70,000-110,000 mi

Symptoms: Plug breaks during removal, porcelain drops into cylinder, Catastrophic engine noise after plug service, Metal shavings in oil, loss of compression across multiple cylinders, Rod knock or bearing failure shortly after plug change

Fix: The 2-piece spark plugs break frequently during removal. If porcelain falls into cylinder and isn't retrieved, it destroys pistons, cylinder walls, and bearings on startup. Requires engine teardown or replacement. Some shops use borescope extraction (4-6 hours), but often it's short block or long block time (18-24 hours).

Estimated cost: $5,000-8,500

Typical onset: 60,000-90,000 mi

Symptoms: Clunking over bumps, especially during turns, Steering wander, vague on-center feel, Inner tire wear, alignment won't hold, Visible torn bushings or play in ball joints on inspection

Fix: MacPherson strut front end uses pressed-in bushings that crack and tear, especially with performance driving. Ball joints wear simultaneously. Most techs replace entire control arms with new assemblies rather than pressing bushings (3-4 hours both sides with alignment). OEM bushings last 60-80k; aftermarket poly lasts longer but transmits more NVH.

Estimated cost: $600-950

Typical onset: 70,000-120,000 mi

Symptoms: Whining or howling from rear end during acceleration or coasting, Clunking when engaging throttle from a stop, Vibration at highway speeds, Metal shavings or burnt smell in differential fluid

Fix: The 8.8-inch rear end is generally stout, but neglected fluid changes (every 30-40k) lead to bearing and gear wear. Limited-slip clutches wear out, causing chatter in turns. Bearing replacement requires axle removal and press work (6-8 hours). Full rebuild with gears runs 10-14 hours. Fluid service is cheap insurance every 30k.

Estimated cost: $800-2,200

Typical onset: Any mileage, age-related

Symptoms: Transmission fluid leaking from radiator area or cooler lines, Pink or red fluid in coolant reservoir (cooler ruptured internally), Transmission slipping or delayed engagement after coolant mixing, Low transmission fluid level, overfilled cooling system

Fix: Steel cooler lines rust through where they connect to radiator. Internal cooler in radiator can rupture, mixing coolant and ATF and destroying the transmission. Requires immediate shutdown if mixing occurs. Line replacement takes 2-3 hours; if trans contaminated, flush and fluid change or full rebuild. Many owners install external coolers as prevention.

Estimated cost: $300-600 for lines, $3,500+ if transmission contaminated

Symptoms: Recall notice from Ford for driver and passenger airbags, No symptoms until deployment, then inflator can rupture with metal shrapnel, Airbag light may illuminate if module has internal fault

Fix: Multiple recalls for Takata inflators on driver and passenger airbags. These MUST be addressed — inflators degrade over time and can explode violently, sending metal fragments into cabin. Replacement is free at Ford dealers, takes 1-2 hours per side. Check VIN on NHTSA site and get it done.

Estimated cost: $0 (recall repair)