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2004 Chevrolet Avalanche

Owner reports · Recalls · Investigations

More warning signs than most Avalanche years

Owner complaints for the 2004 Chevrolet Avalanche are substantially higher than the model-year median of 82.

About this comparison →

When problems were reported

Mileage at the reported incident

140 reports with mileage · 25 unknown

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Electrical System. Review the 60 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Service Brakes. Review the 25 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Service Brakes, Hydraulic. Review the 15 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

6 crash reports1 fire reports3 injury reports

What owners actually said

165 reports
80,000 miles · Jan 14, 2009
Electrical System

FAILURE HAS OCCURRED TWICE ON MY 2004 AVALANCHE SURROUNDING THE INEFFICIENCIES WITHIN MY DASH BOARD. THE SPEEDOMETER WAS READING INCORRECTLY. IT WAS VERY DANGEROUS AS THE ACCURATE SPEED WAS NOT REPORTING. I WAS ABLE TO GET THIS REPLACED AT ABOUT 40,000 MILES. RECENTLY, THE GAS GAUGE IS NOT WORKING CORRECTLY. AFTER FILLING U…

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FAILURE HAS OCCURRED TWICE ON MY 2004 AVALANCHE SURROUNDING THE INEFFICIENCIES WITHIN MY DASH BOARD. THE SPEEDOMETER WAS READING INCORRECTLY. IT WAS VERY DANGEROUS AS THE ACCURATE SPEED WAS NOT REPORTING. I WAS ABLE TO GET THIS REPLACED AT ABOUT 40,000 MILES. RECENTLY, THE GAS GAUGE IS NOT WORKING CORRECTLY. AFTER FILLING UP THE TANK AND TAKING A ROAD TRIP THE GAS GAUGE IMMEDIATELY REPORTED AN EMPTY GAS READING. THE GAS GAUGE CONTINUES TO READ INCORRECTLY AND FLUCTUATES. I HAVE CONTACTED THE COMPANY TO FIND OUT THAT THERE IS A SERVICE WARRANTY ON THE VEHICLE UP TO ABOUT 70,000 MILES. CURRENTLY MY TRUCK IS AT 86000 MILES ALL DUE TO HIGHWAY TRAFFIC TO WORK (30 MILES EACH WAY). I DO NOT FEEL THAT I SHOULD EXPENSE THIS COST SINCE THIS IS CLEARLY A FACTORY ISSUE. REGARDLESS OF THE NUMBER OF MILES ON THE VEHICLE IF IT IS A KNOWN DEFECT IT SHOULD BE COVERED. THIS IS VERY DANGEROUS AS I COULD RUN OUT OF GAS ON THE ROAD. THIS IS ALSO VERY DISAPPOINTING AS THIS DEPICTS THE QUALITY OF THE VEHICLE. MY FATHER HAS BOUGHT NOTHING BUT CHEVROLET'S OVER THE YEARS AND STATES HOW EFFICIENT THE VEHICLES ARE. IN ADDITION I HAVE ALREADY REPLACED THE ENTIRE DASH BOARD ONCE FROM THE FIRST INCIDENT SURROUNDING THE SPEEDOMETER TO HAVE RECEIVED ANOTHER DEFECTIVE DASH BOARD SURROUNDING THE GAS GAUGE. *TR

NHTSA ODI #10255066

Mileage unknown · Jan 8, 2009
Engine And Engine Cooling

MY 2004 AVALANCHE IS SMOKING COMING FROM THE TAIL PIPE WHEN I START IT. *TR

NHTSA ODI #10254290

50,800 miles · Jan 6, 2009
Electrical System

TL*THE CONTACT OWNS A 2004 CHEVROLET AVALANCHE. THE CONTACT STATED THAT THE SPEEDOMETER FAILED TO WORK AT ALL SPEEDS. THE FAILURE HAS OCCURRED A COUPLE OF TIMES. HE FELT THAT IT WAS A SAFETY ISSUE THAT COULD LEAD TO TRAFFIC TICKETS AND A CRASH. THE CURRENT AND FAILURE MILEAGES WERE 50,800.

NHTSA ODI #10254038

50,800 miles · Jan 6, 2009
Electrical System

TL*THE CONTACT OWNS A 2004 CHEVROLET AVALANCHE. THE CONTACT STATED THAT THE SPEEDOMETER FAILED TO WORK AT ALL SPEEDS. THE FAILURE HAS OCCURRED A COUPLE OF TIMES. HE FELT THAT IT WAS A SAFETY ISSUE THAT COULD LEAD TO TRAFFIC TICKETS AND A CRASH. THE CURRENT AND FAILURE MILEAGES WERE 50,800.

NHTSA ODI #10254030

38,000 miles · Dec 31, 2008
Electrical System

WHILE DRIVING APPROXIMATELY 50 MPH MY SPEEDOMETER BEGAN TO READ 120 MPH. I CONSIDER IT A DRIVING HAZARD (SAFETY) WHEN DRIVING ON THE HIGHWAY AND IN TRAFFIC. VERY DISTRACTING. WHEN I INVESTIGATED ON-LINE I DISCOVERED THAT THIS IS A WELL DOCUMENTED DEFECT. THE COST FOR REPAIR IS OVER $400 AND SHOULD NOT BE BOURN BY THE CONSU…

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WHILE DRIVING APPROXIMATELY 50 MPH MY SPEEDOMETER BEGAN TO READ 120 MPH. I CONSIDER IT A DRIVING HAZARD (SAFETY) WHEN DRIVING ON THE HIGHWAY AND IN TRAFFIC. VERY DISTRACTING. WHEN I INVESTIGATED ON-LINE I DISCOVERED THAT THIS IS A WELL DOCUMENTED DEFECT. THE COST FOR REPAIR IS OVER $400 AND SHOULD NOT BE BOURN BY THE CONSUMER FOR A KNOWN DEFECT. *TR

NHTSA ODI #10253351

Mileage unknown · Oct 9, 2008
Service Brakes, HydraulicWheels

WHEN I SLOW DOWN AT LOW RATES OF SPEED, OCCASIONALLY THE BRAKES BEGAN TO PULSATE AS IF IN THE ABS MODE. I WAS TOLD THAT IT WAS BECAUSE OF THE CORROSION ON THE ABS SPEED SENSORS, LOCATED WITHIN THE WHEEL BEARING ASSEMBLY, FORMED BY ROAD SALT. THIS PROBLEM JUST APPEARED WITHOUT WARNING OR PROVOCATION. WHEN OPERATING THE V…

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WHEN I SLOW DOWN AT LOW RATES OF SPEED, OCCASIONALLY THE BRAKES BEGAN TO PULSATE AS IF IN THE ABS MODE. I WAS TOLD THAT IT WAS BECAUSE OF THE CORROSION ON THE ABS SPEED SENSORS, LOCATED WITHIN THE WHEEL BEARING ASSEMBLY, FORMED BY ROAD SALT. THIS PROBLEM JUST APPEARED WITHOUT WARNING OR PROVOCATION. WHEN OPERATING THE VEHICLE AND LOW SPEEDS, STOPPING DISTANCES ARE LENGTHEN BY 10 TO 30 PERCENT. THERE HAS BEEN A RECALL ON THIS TYPE OF VEHICLE FOR SEVERAL YEARS IN OTHER STATES. FOR SOME INEXPLICABLE REASON, IT DOES NOT PERTAIN TO WISCONSIN. EVEN AFTER ALL OF THESE YEARS, THE PART TO REPAIR MY TRUCK REMAINS ON BACKORDER. THE DEALER/MANUFACTURER CAN ONLY PROVIDE THEM IF I PURCHASED THE WHOLE BEARING ASSEMBLY WHICH IS QUADRUPLE THE PRICE OF THE PART THAT I NEED. OF COURSE, I FEEL THAT THIS IS UNFAIR AND WHILE I WAIT FOR THE APPROPRIATE PART TO REPAIR MY TRUCK, I AM PUTTING MY SAFETY, AS WELL AS OTHERS, IN JEOPARDY (THIS IS SAD TO SAY BUT I AM NOT USING PRUDENT DECISION-MAKING SKILLS). I BELIEVE THAT IT IS FAIR TO SAY THAT IF THERE WERE NOT OTHERS IN THE AREA HAVING THIS EXACT SAME PROBLEM, THE PART WOULD NOT BE ON BACKORDER THROUGHOUT THE DEALERSHIPS IN WISCONSIN. I BELIEVE THAT THIS MATTER SHOULD BE LOOK INTO AND ADDRESSED AND REFUNDS GIVEN TO THOSE WHO HAVE PAID THE ENORMOUS PRICE OF THIS REPAIR SIMPLY BECAUSE IT IS A KNOWN DEFECT AND BECAUSE THIS DEFECT IS A SAFETY HAZARDS. *TR

NHTSA ODI #10245020

69,124 miles · Sep 9, 2008
Power TrainService Brakes, HydraulicSuspension

I HAVE PROBLEM WITH THE BRAKE SYSTEM, AND THE TRANSMISSION FLUID CAME OUT FROM THE FROM FRONT PASSENGER SIDE. I TOOK IT TO THE CHEVY DEALER, BUT I WAS TOLD THAT THE TRANSMISSION CLUTCH WAS BURNED OUT, MAYBE IT AN DEFECTED TRANSMISSION OR RECALL, IM NOT SURE, BUT I DO KNOW THAT THE TRANSMISSION AND THE BRAKE SYSTEM ARE NOT IN SAF…

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I HAVE PROBLEM WITH THE BRAKE SYSTEM, AND THE TRANSMISSION FLUID CAME OUT FROM THE FROM FRONT PASSENGER SIDE. I TOOK IT TO THE CHEVY DEALER, BUT I WAS TOLD THAT THE TRANSMISSION CLUTCH WAS BURNED OUT, MAYBE IT AN DEFECTED TRANSMISSION OR RECALL, IM NOT SURE, BUT I DO KNOW THAT THE TRANSMISSION AND THE BRAKE SYSTEM ARE NOT IN SAFE CONDITIONS, NOR WORKABLE. NOT TO MENTION THE CRACKING NOISE IN THE FRONT OF THE SUSPENSION, WHILE TURNING. *TR

NHTSA ODI #10241413

60,000 miles · Aug 19, 2008
Electrical System

OIL GAUGE BEGAN TO SHOW LOW PRESSURE THEN NO PRESSURE. CARRIED TO DEALER, THEY REPLACED OIL SENSOR ON ENGINE. PROBLEM STILL OCCURS BUT ONLY AFTER VEHICLE HAS BEEN DRIVEN FOR A COUPLE OF HOURS STRAIGHT. NOW THE PRESSURE GAUGE PEGS TO THE RIGHT. HOWEVER, ONCE THE VEHICLE HAS BEEN TURNED OFF FOR THE NIGHT, IT PERFORMS CORRECTLY AND…

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OIL GAUGE BEGAN TO SHOW LOW PRESSURE THEN NO PRESSURE. CARRIED TO DEALER, THEY REPLACED OIL SENSOR ON ENGINE. PROBLEM STILL OCCURS BUT ONLY AFTER VEHICLE HAS BEEN DRIVEN FOR A COUPLE OF HOURS STRAIGHT. NOW THE PRESSURE GAUGE PEGS TO THE RIGHT. HOWEVER, ONCE THE VEHICLE HAS BEEN TURNED OFF FOR THE NIGHT, IT PERFORMS CORRECTLY AND I HAVE BEEN UNABLE TO GET IT TO DEMO FOR DEALER AS IT ONLY DOES IT ON LONG TRIPS WHICH OCCUR ON WEEKENDS AND NIGHT. *TR

NHTSA ODI #10238874

56,300 miles · Jun 4, 2008
Electrical System

INSTRUMENT CLUSTER WENT OUT MPH KEPT FLUCTUATING, AND A/C AND HEATING HAS A MIND OF ITS OWN GOES ON AND OFF AND IN STRENGTH OF BLOWING, ALL THIS WHICH I HEAR IS COMMON IN 04 TO 05 CHEVROLET TRUCKS. EVEN A CHEVROLET MECHANIC TOLD ME WHEN FIXING MY TRUCK SAID IT WAS PRETTY COMMON IN THESE YEARS 04- 05 . AND HE DIDN'T KNOW WHY IT D…

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INSTRUMENT CLUSTER WENT OUT MPH KEPT FLUCTUATING, AND A/C AND HEATING HAS A MIND OF ITS OWN GOES ON AND OFF AND IN STRENGTH OF BLOWING, ALL THIS WHICH I HEAR IS COMMON IN 04 TO 05 CHEVROLET TRUCKS. EVEN A CHEVROLET MECHANIC TOLD ME WHEN FIXING MY TRUCK SAID IT WAS PRETTY COMMON IN THESE YEARS 04- 05 . AND HE DIDN'T KNOW WHY IT DOESN'T HAVE A RECALL. *TR

NHTSA ODI #10229841

35,000 miles · Apr 3, 2008
Electrical System

MY SPEEDOMETER QUIT WORKING. THIS IS A KNOWN DEFECT WITH THE 2004 AVALANCHE. OTHER THINGS THAT HAVE WENT WRONG ARE THE GAS GAUGE DOESN'T WORK. THIS TO ME IS A BIG SAFETY ISSUE. YOU CANT TELL HOW FAST YOU ARE GOING. *TR

NHTSA ODI #10223242

Official recalls

5

06V289000 · Engine And Engine Cooling

Aug 3, 2006

ON CERTAIN TRUCKS EQUIPPED WITH AN 8.1L V8 (RPO L8-VIN G) ENGINE HAVE A CONDITION IN WHICH THE ENGINE FUEL RAIL PULSE DAMPER RETAINER CLIP MAY FRACTURE RESULTING IN INADEQUATE RETENTION OF THE DAMPER.

Consequence & remedy

Consequence: IF THE DAMPER COMES LOOSE, A FUEL LEAK MAY RESULT. FUEL LEAKAGE, IN THE PRESENCE OF AN IGNITION SOURCE, COULD RESULT IN A FIRE.

Remedy: DEALERS WILL REPLACE THE ENGINE FUEL RAIL PULSE DAMPER RETAINER CLIP FREE OF CHARGE. THE RECALL BEGAN ON AUGUST 31, 2006. OWNERS MAY CONTACT CHEVROLET AT 1-800-630-2438 AND GMC TRUCKS AT 1-866-996-9463.

05V163000 · Seat Belts:rear/other

Apr 22, 2005

ON CERTAIN CREW CAB PICKUP TRUCKS AND SPORT UTILITY VEHICLES, THE 2ND ROW CENTER OCCUPANT SEAT BELT ROUTING MAY MAKE IT DIFFICULT TO POSITION THE LAP PORTION OF THE SAFETY BELT LOW AROUND THE HIPS OF OCCUPANTS, ESPECIALLY SMALLER OCCUPANTS, SEATED IN THIS POSITION. APPROPRIATE USE OF A CHILD SEAT OR BOOSTER SEAT, AS RECOMMENDED FOR SMALL CHILDREN, DOES IMPROVE THE FIT CONDITION FOR THIS USER GROUP. IN ADDITION TO INSTRUCTIONS ON PROPER INFANT AND YOUNG CHILD RESTRAINT (WITH CHILD SEATS OR BOOSTERS), SPECIAL VERBIAGE FOR RESTRAINING OLDER CHILD IS INCLUDED IN THE OWNER'S MANUAL. ALSO, THE SUGGESTED SEAT BELT FIT/ROUTING FOR ADULTS, IRRESPECTIVE OF SEATING POSITION, IS DESCRIBED IN THE OWNER'S MANUAL TEXT.

Consequence & remedy

Consequence: A LAP PORTION OF THE SEAT BELT ROUTING THAT IS NOT LOW AND SNUG ON THE HIPS CAN ALLOW THE LAP BELT TO RIDE UP ON AN OCCUPANT'S ABDOMEN INSTEAD OF FITTING LOW AROUND THEIR HIPBONES, AND THEREFORE, CAN EXPOSE THEM TO MORE RISK OF ABDOMINAL AND INTERNAL ORGAN INJURY.

Remedy: DEALERS WILL CUT OPEN THE GUIDE LOOP, REMOVE A PORTION OF THE LOOP, AND THEN THE REMAINING TWO SIDES SHOULD BE FOLDED OVER AND SECURED WITH A RETAINER FREE OF CHARGE. THE RECALL BEGAN ON JULY 21, 2005. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339, CHEVROLET AT 1-800-630-2438, GMC AT 1-866-996-9463, OR HUMMER AT 1-800-732-5493.

05V043000 · Service Brakes, Hydraulic

Feb 8, 2005

CERTAIN TRUCKS, SPORT UTILITY VEHICLES, AND VANS EQUIPPED WITH BOSCH HYDRO-BOOST BRAKE ASSEMBLIES, THE HYDRAULIC BRAKE BOOSTER PRESSURE ACCUMULATOR MAY CRACK AND SEPARATE FROM THE HYDRO-BOOST ASSEMBLY DURING NORMAL OPERATING CONDITIONS.

Consequence & remedy

Consequence: IF A SEPARATION OCCURRED AND THE HOOD OF THE VEHICLE WERE OPEN, FRAGMENTS FROM THE ACCUMULATOR COULD CAUSE INJURY TO PEOPLE IN THE IMMEDIATE AREA. THE PRESENCE OF THIS CRACK OR FRACTURED SURFACE COULD ALLOW THE HYDRAULIC FLUID TO LEAK FROM THE ACCUMULATOR CIRCUIT OF THE BOOSTER ASSEMBLY. THE LOSS OF FLUID WOULD CAUSE INCREASED STEERING AND BRAKING EFFORT AND A CRASH MAY OCCUR WITHOUT PRIOR WARNING.

Remedy: DEALERS WILL TEST THE HYDRO-BOOST ASSEMBLY FOR FUNCTIONAL OPERATION OF THE TWO-FUNCTION VALVE. IF THE HYDRO-BOOST ASSEMBLY FAILS THE TEST, DEALERS WILL REPLACE THE ASSEMBLY FREE OF CHARGE. THE RECALL BEGAN ON MARCH 23, 2005. OWNERS MAY CONTACT CHEVROLET AT 1-800-630-2438, GMC TRUCKS AT 1-866-996-9463 AND HUMMER AT 1-800-732-5493.

04V129000 · Structure:body:tailgate:hinge And Attachments

Mar 17, 2004

ON CERTAIN PICKUP TRUCKS AND SPORT UTILITY VEHICLES, THE GALVANIZED STEEL TAILGATE SUPPORT CABLES THAT RETAIN THE TAILGATE IN THE FULL OPEN (HORIZONTAL) POSITION MAY CORRODE, WEAKEN, AND EVENTUALLY FRACTURE. IF BOTH CABLES FRACTURED, THE TAILGATE WOULD SUDDENLY DROP AND STRIKE THE TOP SURFACE OF THE REAR BUMPER.

Consequence & remedy

Consequence: ANYONE SITTING OR STANDING ON THE HORIZONTAL SURFACE OF THE TAILGATE WHEN BOTH CABLES FRACTURED COULD BE INJURED BY FALLING FROM THE TAILGATE. ON VEHICLES THAT HAVE HAD THE BUMPER REMOVED, THE TAILGATE MAY DROP EVEN LOWER. ADDITIONALLY, IF THERE IS CARGO ON THE TAILGATE THE CARGO MAY FALL OFF IF THE SUPPORT CABLES FRACTURE.

Remedy: DEALERS WILL REPLACE THE CABLES. INTERIM OWNER NOTIFICATION BEGAN ON APRIL 7, 20004. THE RECALL BEGAN ON SEPTEMBER 24, 2004, WHEN REPLACEMENT PARTS WERE AVAILABLE, AND WILL CONTINUE THROUGH OCTOBER 29, 2004. OWNERS SHOULD CONTACT CADILLAC AT 1-866-982-2339, CHEVROLET AT 1-800-630-2438 OR GMC AT 1-866-996-9463, OR VISIT WWW.MYGMLINK.COM, AND ENTER YOUR VEHICLE IDENTIFICATION NUMBER.

04V045000 · Service Brakes, Hydraulic

Feb 4, 2004

CERTAIN SPORT UTILITY VEHICLES, PICKUP TRUCKS, AND PASSENGER VANS FAIL TO COMPLY WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 135, ?PASSENGER CAR BRAKE SYSTEMS.? SOME OF THESE VEHICLES WERE PRODUCED WITH AN OUT-OF-SPECIFICATION BRAKE HYDRO-BOOST HOUSING RELIEF VALVE BORE.

Consequence & remedy

Consequence: CONSEQUENTLY, THE VALVE O-RING SEAL MAY FRACTURE. STEERING EFFORTS MAY BE SLIGHTLY INCREASED WHILE BRAKING OR PARKING. UNDER CERTAIN DRIVING CONDITIONS, A FRACTURED SEAL MAY REQUIRE A SLIGHT INCREASE IN THE APPLIED BRAKE PEDAL EFFORT TO ACHIEVE THE SAME VEHICLE DECELERATION RATE AS PRIOR TO THE SEAT FRACTURE.

Remedy: DEALERS ARE TO REPLACE THE HYDRO-BOOST RELIEF VALVE. THE RECALL BEGAN ON JUNE 18, 2004. OWNERS SHOULD CONTACT CADILLAC AT 1-866-982-2339; CHEVROLET AT 1-800-630-2438; GMC AT 1-866-996-9463; OR HUMMER AT 1-866-486-6376.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

1

EA04012 · Hydraulic Pump Failres

Opened Apr 30, 2004 · Closed Feb 28, 2005

Status: closed (inferred from source dates) · Service Brakes, Hydraulic:power Assist; Steering:hydraulic Power Assist System

GM IS CONDUCTING A RECALL ON ALL SUBJECT VEHICLES BUILD BETWEEN MAY 1999 AND OCTOBER 14, 1999.SIGNIFICANT CHANGES WERE INCORPORATED INTO PRODUCTION IN EARLY OCTOBER 1999, AND VEHICLES BUILT AFTER THAT DATE HAVE LOWER WARRANTY FAILURE RATES.THE COMPLAINT AND WARRANTY DATA APPEAR TO SUPPORT THE EFFECTIVENESS OF THESE CHANGES. GM MADE ADDITIONAL CHANGES IN NOVEMBER 1999, FEBRUARY 2000, MAY 2001, AND FEBRUARY 2004.ODI WILL CONTINUE TO MONITOR THIS PROBLEM AND WILL TAKE FURTHER ACTION, IF WARRANTED, IN THE FUTURE.FOR FURTHER TECHNICAL DETAILS SEE THE ATTACHED ENGINEERING ANALYSIS REPORT.

Additional source detail variants (2)

Service Brakes, Hydraulic:power Assist

GM IS CONDUCTING A RECALL ON ALL SUBJECT VEHICLES BUILD BETWEEN MAY 1999 AND OCTOBER 14, 1999.SIGNIFICANT CHANGES WERE INCORPORATED INTO PRODUCTION IN EARLY OCTOBER 1999, AND VEHICLES BUILT AFTER THAT DATE HAVE LOWER WARRANTY FAILURE RATES.THE COMPLAINT AND WARRANTY DATA APPEAR TO SUPPORT THE EFFECTIVENESS OF THESE CHANGES. GM MADE ADDITIONAL CHANGES IN NOVEMBER 1999, FEBRUARY 2000, MAY 2001, AND FEBRUARY 2004.ODI WILL CONTINUE TO MONITOR THIS PROBLEM AND WILL TAKE FURTHER ACTION, IF WARRANTED, IN THE FUTURE.FOR FURTHER TECHNICAL DETAILS SEE THE ATTACHED ENGINEERING ANALYSIS REPORT.

Steering:hydraulic Power Assist System

GM IS CONDUCTING A RECALL ON ALL SUBJECT VEHICLES BUILD BETWEEN MAY 1999 AND OCTOBER 14, 1999.SIGNIFICANT CHANGES WERE INCORPORATED INTO PRODUCTION IN EARLY OCTOBER 1999, AND VEHICLES BUILT AFTER THAT DATE HAVE LOWER WARRANTY FAILURE RATES.THE COMPLAINT AND WARRANTY DATA APPEAR TO SUPPORT THE EFFECTIVENESS OF THESE CHANGES. GM MADE ADDITIONAL CHANGES IN NOVEMBER 1999, FEBRUARY 2000, MAY 2001, AND FEBRUARY 2004.ODI WILL CONTINUE TO MONITOR THIS PROBLEM AND WILL TAKE FURTHER ACTION, IF WARRANTED, IN THE FUTURE.FOR FURTHER TECHNICAL DETAILS SEE THE ATTACHED ENGINEERING ANALYSIS REPORT.