TSB
98-5A-4 |
- BRAKES - PREVENTING BRAKE VIBRATION - SERVICE TIP
- WHEELS - PROPER LUG TORQUE PROCEDURES - SERVICE TIP
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| Publication Date: MARCH 18, 1998 |
FORD: | 1972-1997 THUNDERBIRD
1976-1986 LTD
1976-1997 MUSTANG
1981-1997 CROWN VICTORIA
1982-1988 EXP
1982-1998 ESCORT
1984-1994 TEMPO
1986-1997 TAURUS
1988-1993 FESTIVA
1989-1997 PROBE
1994-1997 ASPIRE
1995-1998 CONTOUR |
LINCOLN-MERCURY: | 1979-1983 MONARCH, ZEPHYR
1979-1997 COUGAR
1980-1983 MARK VI
1980-1998 CONTINENTAL, TOWN CAR
1981-1986 LYNX
1983-1986 MARQUIS
1984-1992 MARK VII
1984-1994 TOPAZ
1986-1997 SABLE
1987-1989 TRACER
1987-1997 GRAND MARQUIS
1991-1994 CAPRI
1991-1997 TRACER
1993-1998 MARK VIII
1995-1998 MYSTIQUE |
LIGHT TRUCK: | 1979-1996 BRONCO
1979-1997 ECONOLINE, F-150-350 SERIES
1984-1990 BRONCO II
1984-1997 RANGER
1986-1997 AEROSTAR
1988-1997 F SUPER DUTY
1991-1997 EXPLORER
1993-1997 VILLAGER
1995-1998 WINDSTAR
1997 EXPEDITION
1998 NAVIGATOR |
ISSUE:
The use of air impact tools to tighten wheel lug nuts can lead to overtightened and/or unevenly tightened wheel lug nuts. Air impact tools typically used for wheel lug nut removal and installation can generate up to 475 N-m (350 lb-ft) of torque. Overtightened and/or unevenly torqued wheel lug nuts may cause: - Brake vibration
- Distortion of the wheel hub
- Distortion of the brake rotor
- Brake rotor runout
- Damage to the wheel
- Damage to the wheel nuts and studs
ACTION:
All wheel lug nuts should only be tightened to specification using a torque wrench or by using the Rotunda ACCUTORQ 164-R0314 or equivalent on a 1/2" drive air impact tool. The "ACCUTORQ" lug nut sockets limit the torque of the air impact tool, preventing overtightening or uneven tightening of the wheel lug nuts. The torque limiting devices (regulators) on air impact tools will not reduce the output torque enough to prevent overtightening of the wheel lug nuts.
| NOTE: | REFER TO THE APPROPRIATE SERVICE MANUAL OR THE CHART IN FIGURE 1 FOR THE CORRECT WHEEL LUG NUT TORQUE SPECIFICATION. THE CHART IN FIGURE 1 ALSO PROVIDES THE CORRECT "ACCUTORQ" LUG NUT SOCKET TO USE. |
Figure 1 - Article 98-5A-4
The "ACCUTORQ" socket is intended for lug nut installation, not removal. When using the "ACCUTORQ" socket, the output torque of the air impact tool must be set to 217-339 N-m (160-250 lb-ft), usually this will be the lowest setting on the air impact tool. The "ACCUTORQ" lug nut sockets are available through Rotunda Equipment. The four-piece set (164-R0314) fits most Ford Motor Company cars and light trucks. The tool set consists of four (4) lug nut sockets and a storage case. The set can be ordered by calling Rotunda Equipment at 1-800-ROT-UNDA (768-8632).
 | CAUTION: | AIR IMPACT TOOLS SHOULD NOT BE USED TO TIGHTEN WHEEL LUG NUTS UNLESS THE "ACCUTORQ" LUG NUT SOCKET OF THE CORRECT SPECIFICATION IS USED. |
| NOTE: | DO NOT USE AIR IMPACT TOOLS ON LOCKING WHEEL LUG NUTS. THEY ARE TO BE HAND-TORQUED ONLY. |
OTHER APPLICABLE ARTICLES:NONE
SUPERSEDES:97-17-6
WARRANTY STATUS:Information Only
OASIS CODES:301000, 303000, 306000
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