The 2004 Impala is a workhorse W-body sedan that's affordable to own until the 3.8L Series II engine consumes itself or the 4T65-E transmission decides it's done. Intake manifold gaskets and transmission cooler lines are your bread-and-butter on these.
3.8L Series II Lower Intake Manifold Gasket Failure
Common · high severity
Typical onset: 80,000-140,000 mi
Symptoms: Coolant loss with no visible external leaks, White smoke from exhaust on cold start, Rough idle or misfire codes, Milky oil on dipstick if severe
Fix: Replace lower intake manifold gaskets, upper plenum gaskets, and coolant while you're in there. This is a 4-5 hour job if nothing breaks. Budget extra time if manifold bolts snap—common on rusty examples. Use Fel-Pro or OEM gaskets, not cheap parts-store sets.
Estimated cost: $600-1,200
4T65-E Transmission Internal Cooler Line Failure
Common · high severity
Typical onset: 90,000-150,000 mi
Symptoms: Pink milkshake in coolant reservoir, Transmission slipping or delayed engagement, Overheating transmission, Sudden loss of forward gears
Fix: The cooler line inside the radiator side tank corrodes and mixes coolant with ATF. Once compromised, the transmission is on borrowed time—flush won't save it. Requires transmission rebuild or replacement (8-12 hours R&R plus rebuild time) plus new radiator. If caught early and trans still shifts fine, some techs try a flush and external cooler, but it's gambling.
Estimated cost: $2,500-4,500
Passlock II Anti-Theft System No-Start
Common · medium severity
Symptoms: Engine cranks but won't start, Security light flashing or staying on, Starts after waiting 10 minutes, Intermittent no-start in cold or damp weather
Fix: The ignition lock cylinder sensor fails and thinks someone's stealing the car. GM's relearn procedure (leave key on for 10 min, off for 5 sec, repeat 3x) sometimes works. Permanent fix is replacing the lock cylinder assembly (1.5 hours) or installing a resistor bypass—though bypass disables the theft deterrent. I've seen guys do the resistor trick in 30 minutes, but it voids any remaining security.
Estimated cost: $250-500
Engine Oil Consumption / Piston Ring Failure (3.8L)
Occasional · high severity
Typical onset: 120,000-180,000 mi
Symptoms: Burning a quart every 500-800 miles, Blue smoke on acceleration, Fouled spark plugs, Low compression on cylinder leak-down test
Fix: The Series II 3.8L can carbons up the rings or wears the ring lands. Once it's drinking oil, you're looking at engine rebuild or replacement. A proper rebuild with machine work, pistons, rings, bearings, gaskets is 18-24 hours. Short block swap cuts it to 12-16 hours but parts cost more. Many owners just ride it out adding oil until something else breaks.
Estimated cost: $3,000-5,500
Front Transmission Mount Failure
Common · low severity
Typical onset: 70,000-120,000 mi
Symptoms: Clunk when shifting from Park to Drive, Vibration at idle in gear, Engine rocks excessively during acceleration, Visible torn rubber on mount
Fix: The torque strut mount up top fatigues and the transmission can shift around. It's a 1-hour job, accessible from the top. Replace it before it tears completely and causes driveline vibration or damages cooler lines.
Estimated cost: $150-300
Fuel Pump Failure
Occasional · high severity
Typical onset: 100,000-160,000 mi
Symptoms: No start, cranks but won't fire, Stalling at idle or under load, Whining noise from rear seat area, Loss of fuel pressure
Fix: Pump dies, usually without warning. It's in the tank, requires dropping the tank or cutting an access panel in the trunk floor (some techs do this, not factory-approved). Tank drop is 2-3 hours. Use AC Delco or Delphi pump assemblies—cheap aftermarket pumps fail within a year.
Estimated cost: $500-900
Owner tips
Check coolant reservoir for pink tint every oil change—early warning for trans cooler failure
Replace intake manifold gaskets preemptively around 100k if you plan to keep it long-term
Use Dex-Cool coolant only, flush every 5 years—mixing orange and green eats gaskets faster
The 3.4L is a less common engine option but has head gasket issues around 90-120k; not worth fixing at that point
Buy one under $3,000 with service records and plan for intake gaskets—anything more and you're gambling on a transmission time bomb.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
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General Motors LLC (GM) is recalling certain model year 1998-1999 Chevrolet Lumina and Oldsmobile Intrigue, 1997-2004 Buick Regal and Pontiac Grand Prix, 2000-2004 Chevrolet Impala, and 1998-2004 Chevrolet Monte Carlo vehicles. The affected vehicles were previously repaired under recalls 08V-118, 09V-116, and 15V-201 to address the possibility that engine oil may drip onto the hot exhaust manifold.
Consequence: Engine oil that drips onto the hot surface of the exhaust manifold may result in a fire.
Remedy: The remedy applied under recalls 08V-118, 09V-116, and 15V-201 did not adequately remove the safety risk. Under the improved remedy, dealers will replace the engines front valve cover and gasket. Vehicles that are covered by recalls 08V-118, 09V-116, or 15V-201 that have not yet received the original remedy will instead receive the improved remedy under the original recall number. The recall began on February 19, 2016. Owners may contact Chevrolet customer service at 1-800-222-1020, Buick customer service at 1-800-521-7300, Oldsmobile customer service at 1-800-442-6537 and Pontiac customer service at 1-800-458-8006. GM's number for this recall is 15757. Note: Until the improved remedy has been applied, owners are advised to park their vehicle outside since the fire risk exists even when the vehicle is unattended.
ENGINE AND ENGINE COOLING:ENGINE · 15V201000
2015-04-06
General Motors LLC (GM) notified the agency on April 2, 2015, that they are is recalling certain model year 2004 Buick Regal vehicles manufactured April 9, 2003, to June 1, 2003, 2004 Chevrolet Impala vehicles manufactured April 8, 2003, to June 23, 2003, and 2004 Chevrolet Monte Carlo vehicles manufactured April 7, 2003, to June 23, 2003. On May 18, 2015, GM expanded the recall to cover an additional 49,751 2004 Pontiac Grand Prix vehicles manufactured January 6, 2003, to June 25, 2004. In the affected vehicles, the valve cover gasket may leak.
Consequence: The leaking engine oil can drip onto the hot surface of the exhaust manifold, increasing the risk of a fire.
Remedy: GM will notify owners, and dealers will remove the plastic cover and plastic oil fill tube extension and replace the front valve cover and gasket. These repairs will be done free of charge. The recall began on April 24, 2015. Owners may contact Buick customer service at 1-800-521-7300, Pontiac customer service at 1-800-762-2737 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 14574.
ELECTRICAL SYSTEM:IGNITION · 14V400000
2014-07-03
This defect can affect the safe operation of the airbag system. Until this recall is performed, customers should remove all items from their key rings, leaving only the ignition key. The key fob (if applicable), should also be removed from the key ring.
General Motors LLC (GM) notified the agency on July 3, 2014, that they are recalling 5,877,718 model year 2000-2005 Chevrolet Impala and Monte Carlo, 1997-2003 Chevrolet Malibu, 2004-2005 Malibu Classic, 1999-2004 Oldsmobile Alero, 1998-2002 Oldsmobile Intrigue, 1999-2005 Pontiac Grand Am and 2004-2008 Pontiac Grand Prix vehicles. In these models, the weight on the key ring and/or road conditions or some other jarring event may cause the ignition switch to move out of the run position, turning off the engine.
Consequence: If the key is not in the run position, the air bags may not deploy if the vehicle is involved in a crash, increasing the risk of injury.
Remedy: GM will notify owners, and dealers will install two key rings and an insert in the key slot or a cover over the key head on all ignition keys, free of charge. The recall began on September 9, 2014. GM's number for this recall is 14350.
STEERING · 09E005000
2009-02-17
DORMAN IS RECALLING 979 STEERING KNUCKLES, DORMAN P/NOS. 697-902 AND 697-903, SOLD UNDER DORMAN'S "OE SOLUTIONS<SUP>TM</SUP>" BRAND NAME, AND NAPA P/NOS. 7-8502 AND 7-8503 WHICH WERE SOLD FOR REPLACEMENT USE ON THE VARIOUS VEHICLES LISTED ABOVE. A POTENTIAL MATERIAL OR DESIGN DEFECT COULD RESULT IN THE STEERING KNUCKLE BREAKING IN THE HUB AREA.
Consequence: A BROKEN STEERING KNUCKLE COULD RESULT IN LOSS OF STEERING CONTROL AND A POSSIBLE CRASH WITHOUT WARNING.
Remedy: DORMAN WILL NOTIFY OWNERS AND REPLACE THE DEFECTIVE STEERING KNUCKLES FREE OF CHARGE AND REIMBURSE THE REPAIR FACILITY OR OWNER FOR LABOR. THE RECALL BEGAN ON FEBRUARY 23, 2009. OWNERS MAY CONTACT DORMAN'S TOLL-FREE HOTLINE AT 1-800-523-2492 AND PRESS 5.
STEERING · 08E063000
2008-10-17
DORMAN PRODUCTS IS RECALLING 3,900 INTERMEDIATE STEERING SHAFTS DORMAN PART NOS. 425-151, 425-152, AND 425-153, (SOLD UNDER DORMAN'S "OE SOLUTIONS" BRAND NAME), BALKAMP #'S 7-3057, 7-3058, 7-3059 (SOLD UNDER THE "NAPA" BRAND NAME), AND PLATINUM PARTS #'S 2425151, 2425152, AND 2425153 MANUFACTURED DURING THE MONTH OF SEPTEMBER 2007. THESE REPLACEMENT STEERING SHAFTS CAN BE USED ON THE VEHICLES LISTED ABOVE. THE WELD CONNECTING THE INNER TUBE TO THE OUTER TUBE MAY BE DEFECTIVE.
Consequence: IF THE WELD FAILS, LOSS OF STEERING COULD RESULT, POSSIBLY RESULTING IN A VEHICLE CRASH.
Remedy: DORMAN WILL NOTIFY OWNERS AND REPLACE THE STEERING SHAFTS FREE OF CHARGE. THE RECALL BEGAN ON OCTOBER 16, 2008. OWNERS MAY CONTACT DORMAN TOLL FREE AT 1-800-523-2492.
CERTAIN DELPHI FUEL PRESSURE REGULATORS, P/NOS. FP10020-11B1, FP10026-11B1, AND FP10027-11B1, SOLD AFTER JANUARY 9, 2007, AS AFTERMARKET EQUIPMENT FOR VARIOUS PASSENGER VEHICLES LISTED ABOVE. THE UNIVERSAL PRESSURE REGULATORS (UPR) WERE PRODUCED WITHOUT AN O'RING AND RETAINER.
Consequence: FUEL MAY LEAK, POSSIBLY RESULTING IN A FIRE.
Remedy: DELPHI WILL NOTIFY OWNERS AND REPLACE THE UPR FREE OF CHARGE. THE RECALL BEGAN ON APRIL 23, 2007. OWNERS CAN CONTACT DELPHI AT 877-411-8770.
SERVICE BRAKES, HYDRAULIC · 04V287000
2004-06-23
CERTAIN PASSENGER VEHICLES WERE PRODUCED WITH LOWER THAN SPECIFIED TORQUE ON BOTH FRONT BRAKE CALIPER TO STEERING KNUCKLE ATTACHMENT BOLTS. WITH IMPROPER TORQUE, THE CLAMP LOAD AT THE JOINT MAY NOT BE ADEQUATE TO PREVENT MOVEMENT BETWEEN THE CALIPER BRACKET AND KNUCKLE.
Consequence: DEPENDING ON WHETHER ONE OR BOTH BOLTS BACKS OUT OR FRACTURES, THE RESULT CAN BE LOCKING OF THE AFFECTED WHEEL DURING BRAKING AND AN ABRUPT STEERING INPUT IN THE DIRECTION OF THE LOCKED WHEEL, REDUCED BRAKING AND NOISE FROM THE AFFECTED WHEEL, OR SEVERING OF A BRAKE HOSE, INCREASED BRAKE PEDAL TRAVEL, AND REDUCED STEERING CONTROL. REDUCED BRAKING OR STEERING CONTROL COULD CAUSE A CRASH.
Remedy: DEALERS ARE TO TIGHTEN BOTH BOLTS TO THE SPECIFIED TORQUE. OWNER NOTIFICATION BEGAN ON JUNE 28, 2004. OWNERS SHOULD CONTACT CHEVROLET 1-800-630-2438 OR PONTIAC 1-800-620-7668.
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