MX-5 Miata L4-1.8L DOHC (1996)
Tires: All Technical Service Bulletins
Tires/Wheels - Vehicle Shakes at High Speeds
Bulletin No.: 002/97
Issued: 08/30/97
Revised
Category
Q
Applicable Model/s
'96-'97 MX-5
Subject:
VEHICLE SHAKES AT HIGH SPEED
APPLICABLE MODELS
1996 - '97 MX-5
DESCRIPTION
An annoying vibration (shake) may occur while driving at 45-60 m.p.h. This concern occurs even if the wheel balance and tire pressure of all the tire
assemblies are within specification.
M-Edition-
M-Edition vehicle equipped with 15" tire and wheel assemblies may be subject to poor uniformity and excessive RFV (Radial Force Variation). To
improve the tire bead fitting, the aluminum wheel has been chrome plated. The tire design has also changed to emphasize ride comfort rather than
driveability.
Other than M-Edition
The RFV (Radial Force Variation) of the 14" tire may be excessive. Radial runout increases when the tire and wheel phase (relation to heavy spots) is
not properly matched, or poor fitting occurs between the tire and the wheel. These factors result in shake. The upper limit of the RFV of the tire has been
decreased to reduce this concern.
Customers complaining of this concern should have the vehicle inspected and, if necessary, repaired.
REPAIR PROCEDURE
1.
Verity concern.
2.
Replace the tire assemblies with known good tires (14" tire assemblies from 95-97 Protege or other models), then test drive the vehicle.
^
If the problem disappears, proceed to step 3.
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If the problem does not disappears, determine the cause according to the NVH Manual.
3.
With problem tire assemblies on the vehicle or a wheel balancer, measure the radial runout of the wheels using a dial indicator. Refer to Fig 1.
^
If the radial runout exceeds the specification (2 mm), replace the wheels with service parts.