Investigations
WHEEL STUD AND NUT
NHTSA SQ SQ00016 — closed, opened 2000-09-15 and involving the FORD EXPEDITION.
NHTSA investigation SQ00016 is a SQ opened on 2000-09-15 and currently closed. The subject of record is FORD EXPEDITION, which places this file inside the Office of Defects Investigation queue for FORD. Latest activity on this investigation was logged on 2001-12-06 — NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.
Investigators summarized the matter as follows: "IN DECEMBER 1999, FORD ISSUED TECHNICAL SERVICE BULLETIN 99-26-3, ENTITLED "INCREASED WHEEL NUT AND STUD SIZE-SERVICE TIP," FOR 2000 MODEL YEAR EXPEDITION, NAVIGATOR, AND CERTAIN F-150 VEHICLES, BUILT ON OR AFTER NOVEMBE..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time. Related FORD files, listed below, give context on whether this is an isolated concern or part of a broader pattern across the brand.
Investigation Summary
IN DECEMBER 1999, FORD ISSUED TECHNICAL SERVICE BULLETIN 99-26-3, ENTITLED "INCREASED WHEEL NUT AND STUD SIZE-SERVICE TIP," FOR 2000 MODEL YEAR EXPEDITION, NAVIGATOR, AND CERTAIN F-150 VEHICLES, BUILT ON OR AFTER NOVEMBER 27, 1999. THESE VEHICLES HAVE INCREASED WHEEL STUD AND NUT DIAMETERS FROM 12MM TO 14MM. THE WHEEL NUT TORQUE WAS INCREASED FROM 100 FT-LB. TO 150 FT-LB., RESPECTIVELY. ODI HAS RECEIVED THREE REPORTS OF WHEELS SEPARATING FROM 2000 MODEL YEAR EXPEDITION VEHICLES, INCLUDING TWO CRASHES. TWO ADDITIONAL REPORTS ALLEGE BROKEN STUDS AND/OR LOOSE WHEEL NUTS. LOOSE WHEEL NUTS CAN ALLOW THE WHEEL TO WOBBLE AND CAUSE WHEEL STUD BREAKAGE. THERE ARE NO SIMILAR ODI REPORTS ON 2000 MODEL YEAR LINCOLN NAVIGATOR VEHICLES. THE FAILURES APPEAR TO BE ATTRIBUTED TO IMPROPER WHEEL NUT TORQUE; HOWEVER, THERE IS NO EVIDENCE THAT THERE ARE TORQUE QUALITY DEFICIENCIES AT THE ASSEMBLY PLANTS. DUE TO THE MILEAGES THE INCIDENTS OCCURRED, IT IS MOST LIKELY THAT IMPROPER WHEEL NUT TORQUES WERE APPLIED DURING SERVICING, BECAUSE IN ALL CASES WHEN LOOSE WHEELS WERE RE-TORQUED TO A LEAST 100 FT-LB., THERE WERE NO FAILURE RE-OCCURRENCES.
About This Investigation Type
Other FORD Investigations
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Timing Belt Failure
Underbody shields detachment
B-Pillar Trim Detachment
Unintended Transmission Downshift and Rear Wheel Lock-up
Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. Learn more.
Read our methodology — how this data is sourced, computed, and verified.