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2002 GMC Sierra 2500

Owner reports · Recalls · Investigations

More warning signs than most Sierra 2500 years

Owner complaints for the 2002 GMC Sierra 2500 are substantially higher than the model-year median of 46.

About this comparison →

When problems were reported

Mileage at the reported incident

114 reports with mileage · 20 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.

  • Service Brakes, Hydraulic. Review the 44 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Service Brakes. Review the 32 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Power Train. Review the 14 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

10 crash reports1 fire reports5 injury reports

Steering complaints

9 reports
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240,000 miles · Dec 19, 2016
Steering

WHILE DRIVING OF A CITY STREET, AT A SLOW RATE (10-15MPH) AND TAKING A SLOW, APPROXIMATELY 90 DEGREE LEFT TURN, I HEARD A LOUD "POPPING/BREAKING SOUND". WHILE MAKING THE TURN, I INITIALLY HAD TURNING CAPABILITIES UNTIL I HEARD THE "POP" SOUND. UPON HEARING THE SOUND, I NO LONGER HAD THE ABILITY TO TURN THE WHEELS TO EITHER DIREC…

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WHILE DRIVING OF A CITY STREET, AT A SLOW RATE (10-15MPH) AND TAKING A SLOW, APPROXIMATELY 90 DEGREE LEFT TURN, I HEARD A LOUD "POPPING/BREAKING SOUND". WHILE MAKING THE TURN, I INITIALLY HAD TURNING CAPABILITIES UNTIL I HEARD THE "POP" SOUND. UPON HEARING THE SOUND, I NO LONGER HAD THE ABILITY TO TURN THE WHEELS TO EITHER DIRECTION. UPON STOPPING AND TURNING OFF THE TRUCK, I FOUND THE PITMAN ARM(CONNECTED TO STEERING BOX AND STEERING BAR) WAS DETACHED FROM THE STEERING BAR BUT STILL ATTACHED TO STEERING BOX. THE BOLT OF THE PITMAN ARM HAD BROKEN OFF CLEANLY FROM THE STEERING BAR, RENDERING MY STEERING CAPABILITIES INEFFECTUAL. ATTACHED IS A PICTURE OF THE PITMAN ARM SHEERED BOLT. I WOULD LIKE TO FILE A COMPLAINT THAT THIS DEFECTIVE PIECE OF MATERIAL COULD HAVE COST DAMAGE TO LIFE, PROPERTY AND POTENTIALLY DEATH OF MYSELF OR OTHERS ON THE ROAD. I WOULD LIKE SOME FORM OF RESTITUTION ON PART OF THE MANUFACTURE. THE TOTAL COST OF THE REPAIR WAS APPROXIMATELY $225 USD. I CAN PROVIDE THE BILL FOR TOWING, MECHANICAL REPAIRS AND COST OF REPLACEMENT PART. *TR

NHTSA ODI #10936174

82,760 miles · Nov 21, 2012
Service BrakesSteering

VEHICLE IS A 2002 GMC HD 2500 PICKUP TRUCK WITH A DURAMAX DIESEL ENGINE, AND 5 SPEED ALLISON TRANSMISSION WHILE DRIVING ON SURFACE STREETS, THE POWER BRAKES AND STEERING BOTH WENT OUT SIMULTANEOUSLY. STOPPING REQUIRED BOTH FEET ON PEDAL, AND STEERING WAS NEARLY IMPOSSIBLE. PROBLEM TRACED TO THE "HYDROBOOST" AND THE POWER STEE…

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VEHICLE IS A 2002 GMC HD 2500 PICKUP TRUCK WITH A DURAMAX DIESEL ENGINE, AND 5 SPEED ALLISON TRANSMISSION WHILE DRIVING ON SURFACE STREETS, THE POWER BRAKES AND STEERING BOTH WENT OUT SIMULTANEOUSLY. STOPPING REQUIRED BOTH FEET ON PEDAL, AND STEERING WAS NEARLY IMPOSSIBLE. PROBLEM TRACED TO THE "HYDROBOOST" AND THE POWER STEERING PUMP. BOTH WERE REPLACED ALONG WITH THE HIGH PRESSURE HOSE. EVIDENTLY, THE PUMP FAILED TO YIELD ANY BOOST PRESSURE, WHICH IN TURN RENDERED POWER STEELING AND BRAKES INOPERATIVE. A VERY DANGEROUS SITUATION. THE TOW TRUCK THAT RESPONDED INDICATED THAT THEY HAVE HAD MULTIPLE FAILURES OF THE SAME ITEMS (87 OT 8 GMC HD TRUCKS) AND IN BLOGS WITH OTHER GMC/CHEVY DIESEL OWNERS IT APPEARS TO BE A COMMON DEFECT. THERE WERE NO NOISES, OR OTHER INDICATOR OF PENDING PROBLEMS. CONTACT WITH THE DEALER REVEALED THAT " I SHOULD CHANGE THE PS FLUID EVERY 2 YEARS: (NOT IN THE MAINTENANCE SECTION OF OWNER MANUAL). *TR

NHTSA ODI #10485398

57,000 miles · Jun 7, 2008
Service Brakes, HydraulicSteering

STARTED MY VEHICLE SO COULD MOVE IT IN FRONT OF MY GARAGE. WHEN I TRIED TO TURN THE STEERING WHEEL WOULDN'T MOVE AND I HAD VERY LIMITED BRAKING POWER. IT TOOK AN EXCEPTIONAL AMOUNT OF PRESSURE ON THE BRAKE PEDAL JUST TO STOP THE VEHICLE AT A VERY LOW SPEED. THANKFULLY NO ONE WAS HURT AND NO PROPERTY DAMAGE OCCURRED. *TR

NHTSA ODI #10230221

80,000 miles · Nov 8, 2007
Steering

TL*THE CONTACT OWNS A 2002 GMC SIERRA 2500 HD. WHILE DRIVING BETWEEN 2-5 MPH, THE STEERING WHEEL STIFFENED WHEN IT WAS TURNED TO THE LEFT. WHEN TURNED TO THE RIGHT, THE STEERING WHEEL BECAME RESISTANT. THE FAILURE DID NOT OCCUR WHEN THE VEHICLE WAS DRIVEN STRAIGHT. THE DEALER STATED THAT THE STEERING VALVE AND STEERING BOX N…

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TL*THE CONTACT OWNS A 2002 GMC SIERRA 2500 HD. WHILE DRIVING BETWEEN 2-5 MPH, THE STEERING WHEEL STIFFENED WHEN IT WAS TURNED TO THE LEFT. WHEN TURNED TO THE RIGHT, THE STEERING WHEEL BECAME RESISTANT. THE FAILURE DID NOT OCCUR WHEN THE VEHICLE WAS DRIVEN STRAIGHT. THE DEALER STATED THAT THE STEERING VALVE AND STEERING BOX NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED BECAUSE THE PART WAS UNAVAILABLE. THE FAILURE MILEAGE WAS 80,000 AND CURRENT MILEAGE WAS 81,499.

NHTSA ODI #10208400

37,300 miles · Dec 27, 2006
Exterior LightingPower TrainService Brakes, Hydraulic

TL* - THE CONTACT CALLED ABOUT 2002 GMC SIERRA 2500 HD. HE STATED THAT WHILE APPLYING BRAKES, 7 OUT OF 10 TIMES THE ABS SYSTEM ACTIVATE\D AND PUMPED THE BRAKES. THIS HAPPENED AT ANY TIME OF THE DAY, AND IN ALL WEATHER CONDITIONS. THE CONTACT STATED THAT THIS HAPPENED WHEN APPLYING BRAKES AT ANY SPEED. THE BRAKES PUSHED BAC…

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TL* - THE CONTACT CALLED ABOUT 2002 GMC SIERRA 2500 HD. HE STATED THAT WHILE APPLYING BRAKES, 7 OUT OF 10 TIMES THE ABS SYSTEM ACTIVATE\D AND PUMPED THE BRAKES. THIS HAPPENED AT ANY TIME OF THE DAY, AND IN ALL WEATHER CONDITIONS. THE CONTACT STATED THAT THIS HAPPENED WHEN APPLYING BRAKES AT ANY SPEED. THE BRAKES PUSHED BACK AND THERE WAS A THUMPING NOISE COMING FROM THE MASTER CYLINDER. THE CONTACT LOOKED UP INFORMATION FROM THE NHTSA WEBSITE AND FOUND THAT A RECALL 05V379000 HAD BEEN ISSUED FOR THIS VEHICLE. THE CONTACT SAID THAT HE TOOK VEHICLE TO THE DEALERSHIP, AND WAS TOLD THAT THIS VEHICLE DID NOT FALL UNDER THE RECALL DUE TO VIN. *AK THE INNER TIE ROD HAD EXCESSIVE PLAY, THE FRONT DIFFERENTIAL SEAL WAS LEAKING FROM THE VENT CAP, THE DAYTIME RUNNING LIGHT BULB WAS INOPERATIVE. THE CONSUMER DENIED TO HAVE REPAIRS MADE. UPDATED 01/29/07. *JB

NHTSA ODI #10177052

36,403 miles · Sep 4, 2003
Steering

DIESEL ENGINE QUIT AND IT WAS ONLY EQUIPPED WITH ONE FUSE, AND THE FUSE BLEW. THIS RESULTED IN LOSS OF POWER STEERING AND BRAKES. *AK. THE CONSUMER STATED THE POWER STEERING FAILED AND WHEN THAT FAILED IT CAUSED THE VEHICLE TO HAVE NO BRAKES. *JB

NHTSA ODI #10031948

400 miles · May 9, 2003
SteeringSuspension

VEHICLE PULLS TO THE LEFT ALL THE TIMES. HAVE HAD IT SERVICED 8 TIMES AT PURCHASING DEALER, THEY SAY THEY CAN'T FIX IT. THE STEERING WHEEL IS ALSO OFF AT 1:00 POSITION. *JB

NHTSA ODI #10018445

7,500 miles · Jan 14, 2003
Steering

WHILE DRIVING AT 20/35 MPH, THE VEHICLE PULLED TO THE RIGHT AND THERE WAS NO POWER STEERING. CONSUMER LOST CONTROL OF THE VEHICLE. THIS WAS AS A RESULT OF THE STEERING SHAFT SPLITTING IN HALF. PLEASE PROVIDE MORE DETAILS. TS

NHTSA ODI #10003767

Mileage unknown · Dec 10, 2002
Steering

CONSUMER STATES THE POWER STEERING PUMP SHAFT TWISTED OFF CAUSING LOSS OF POWER STEERING AND BRAKES WHILE DRIVING. TS

NHTSA ODI #8024059

Official recalls

1

01V220000 · Interior Lighting

Jun 26, 2001

VEHICLE DESCRIPTION: CERTAIN PICKUP TRUCKS EQUIPPED WITH 6.6L DIESEL ENGINES FAIL TO COMPLY WITH REQUIREMENTS OF FMVSS NO. 105, "HYDRAULIC AND ELECTRIC BRAKE SYSTEMS." THESE VEHICLES HAVE A BRAKE SYSTEM WARNING LIGHT IN THE INSTRUMENT CLUSTER THAT MAY NOT ILLUMINATE WHEN THE BRAKE FLUID IS LOW. IN ADDITION, WHEN THE BRAKE FLUID IS LOW, THE VEHICLE MAY NOT MEET THE PARTIAL SYSTEM REQUIREMENTS OF FMVSS NO. 105.

Consequence & remedy

Consequence: THESE CONDITIONS COULD RESULT IN REDUCED BRAKING CAPABILITY, WHICH COULD LEAD TO A CRASH.

Remedy: DEALERS WILL CHANGE THE LOCATION OF A WIRE CONNECTION IN THE UNDERHOOD BUSSED ELECTRICAL CENTER. OWNER NOTIFICATION BEGAN JULY 9, 2001. OWNERS WHO TAKE THEIR VEHICLES TO AN AUTHORIZED DEALER ON AN AGREED UPON SERVICE DATE AND DO NOT RECEIVE THE FREE REMEDY WITHIN A REASONABLE TIME SHOULD CONTACT CHEVROLET AT 1-800-222-1020 OR GMC AT 1-800-462-8782.

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

3

EA07013 · Trailer Hitch Receiver Failure

Opened Sep 14, 2007 · Closed Sep 12, 2008

Status: closed (inferred from source dates) · Trailer Hitches

COMPLAINT REPORTS ALLEGE POOR WELD QUALITY AND/OR BENDING OF THE SUBJECT VEHICLE ORIGINAL EQUIPMENT TRAILER HITCH RECEIVER.THE AGENCY'S INVESTIGATION INCLUDED ANALYSIS OF MANUFACTURER AND AGENCY INCIDENT REPORTS, REVIEW OF POLICE REPORTS, ANALYSIS OF THE AGENCY'S FATAL ANALYSIS REPORTING SYSTEM, A VEHICLE OWNER SURVEY, INSPECTION OF TOW VEHICLES/HITCHES AND ANALYSIS OF FAILED PARTS.INCIDENTS OF WELD FAILURE WERE RARE AND ASSOCIATED WITH VERY LOW-SPEED DRIVING (TURNING, BACKING AND SUDDEN STOPPING).INCIDENTS OF BENDING WERE ASSOCIATED WITH IMPROPER TRAILER HITCH ADJUSTMENT OR OVERLOADING. A SAFETY-RELATED DEFECT HAS NOT BEEN IDENTIFIED AT THIS TIME AND FURTHER USE OF AGENCY RESOURCES DOES NOT APPEAR TO BE WARRANTED.ACCORDINGLY, THIS INVESTIGATION IS CLOSED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST.THE AGENCY WILL MONITOR THIS ISSUE AND RESERVES THE RIGHT TO TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES.SEE DOCUMENT SEARCH FILE FOR ADDITION INFORMATION.

PE07025 · Trailer Hitch Receiver Failure

Opened May 14, 2007 · Closed Sep 14, 2007

Status: closed (inferred from source dates) · Trailer Hitches

GM PROVIDED ADDITIONAL DATA REGARDING ALLEGATIONS OF FAILURE OF THE TRAILER HITCH.ODI REVIEWED THAT AS WELL AS OTHER DATA PROVIDED BY PEER MANUFACTURERS.BASED ON OUR REVIEW, ODI FINDS THE NEED TO FURTHER INVESTIGATE THIS ISSUE.THIS PRELIMINARY EVALUATION IS UPGRADED TO AN ENGINEERING ANALYSIS (EA07-013) FOR FURTHER ASSESSMENT AND STUDY OF THIS ISSUE.

PE04004 · Hydraulic Pump Shaft Failures

Opened Jan 8, 2004 · Closed Apr 30, 2004

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

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.

Additional source detail variants (5)

Service Brakes, Hydraulic

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.

Service Brakes, Hydraulic:power Assist

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.

Service Brakes, Hydraulic:power Assist:hydraulic

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.

Steering:hydraulic Power Assist:pump

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.

Steering:hydraulic Power Assist System

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.