Villager V6-201 3.3L SOHC VIN T SFI (1999)
the illustration. Mark the high point of radial runout of the tire on the sidewall, and mark the high point of radial runout of the wheel on the wheel face
for future reference.
Tire Lead
Lead is the deviation of the vehicle from a straight path on a level road with no pressure on the steering wheel. Lead can be caused by:
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incorrect wheel alignment.
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dragging brakes.
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incorrect/uneven tire pressures.
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defective tires.
If defective tires are suspected in a lead condition, use the following steps to determine the defective tire:
1. Rotate the two front tires.
2. Road test the vehicle. If the vehicle leads to the opposite direction, one of the front tires is at fault.
3. Rotate the two front tires back to their original position.
4. Rotate one of the front tires with its corresponding rear tire on the same side of the vehicle.
5. Road test the vehicle. If the lead is corrected, install a new tire in the position that was rotated to the rear. If the lead remains, install a new tire on
the opposite side of the vehicle.
Road Test
NOTE: For a complete road test procedure, refer to Noise, Vibration, and Harshness.
The road test and customer interview (if available) will provide much of the information needed to find the source of a vibration. During the road test,
drive the vehicle on a road that is smooth and free of ruts or crowning. If vibration occurs, note and record the following:
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the speed at which the vibration occurs
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What type of vibration occurs in each speed range - mechanical or audible
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how the vibration is affected by changes in vehicle specifications, engine speed and engine torque
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type of vibration sensitivity - torque - sensitive, vehicle speed-sensitive or engine speed-sensitive
Use the following explanation of terms to help isolate the source of the vibration.
Torque-Sensitive
The condition can be improved or worsened by accelerating, decelerating, coasting or maintaining a steady vehicle speed and applying engine torque.
Vehicle Speed-Sensitive
The vibration always occurs at the same vehicle speed and is not affected by engine torque, engine speed or gear selection.
Engine Speed-Sensitive
The vibration occurs at varying vehicle speeds when a different gear is selected. It can sometimes be isolated by increasing or decreasing engine speed
with the transaxle in N (neutral) or by stall testing with the transaxle in gear. If the condition is engine speed-sensitive, the condition is not related to
the tires.
If the road test indicates that there is tire whine, but no shake or vibration, the noise originates with the contact between the tire and the road. Tire
whine can be distinguished from wheel bearing noise because wheel bearing noise is diminished or changes according to load or speed. Tire noise
remains the same over a range of speeds.
A thumping noise usually means that the tire has flat or soft spots making a noise as they slap the roadway.
To verify that tire noise is not associated with shake or vibration, inflate the tires one at a time to 345 kPa (50 psi) and check for a change in the
sound. The pitch or whine will change as the increased pressure changes the tire frequency.
CAUTION: Be sure to deflate tires to their proper pressures after this check is completed.