Lead/pull is the deviation of the vehicle from a straight path on a level road with no pressure on the steering wheel. Lead is usually caused by the following conditions:
| • | Poor tire construction |
| • | Uneven brake assemblies |
| • | Improper tire and wheel alignment In the front tires (rear tires will not cause lead) |
Tire construction can be a cause of lead in a vehicle. An example of this is placement of the belt. Off-center belts on radial tires can cause the tire to develop a side force while rolling straight down the road, and the tire will tend to roll like a cone.
Use the lead/pull correction table in order to verify that improper tire and wheel alignment is not mistaken for tire lead.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Road test the vehicle in order to verify the complaint Does the vehicle lead/pull to either the left or to the right? | -- | -- | |
2 |
Does the vehicle still lead/pull in the same direction? | 210 kPa (30 psi) | If left, go to Step 3 If right, go to Step 4 | -- |
3 | Vehicle lead or pull is to the left.
Does the vehicle still lead/pull in the same direction? | -- | ||
4 | Vehicle lead or pull is to the right.
Does the vehicle still lead/pull in the same direction? | -- | ||
5 |
Does the vehicle still lead/pull in the same direction? | -- | ||
6 |
Does the vehicle still lead/pull in the same direction? | -- | ||
7 | Perform vehicle alignment. Refer to Wheel Alignment Measurement in Wheel Alignment. Is alignment within specifications? | -- | ||
8 | Replace the left front tire. Is the repair complete? | -- | -- | |
9 | Replace the right front tire. Is the repair complete? | -- | -- | |
10 | Replace the left rear tire. Is the repair complete? | -- | -- | |
11 | Replace the right rear tire. Is the repair complete? | -- | -- | |
12 | Perform vehicle alignment. Refer to Wheel Alignment Measurement in Wheel Alignment. Is repair complete? | -- | -- | |
13 |
Does the vehicle lead/pull to either the left or to the right? | -- | If left, go to Step 14 If right, go to Step 15 | -- |
14 | Vehicle lead/pull is to the left.
Does the vehicle still lead/pull? | -- | System OK | |
15 | Vehicle lead/pull is to the right.
Does the vehicle still lead/pull? | -- | System OK | |
16 |
Does the vehicle still lead/pull? | -- | System OK | |
17 | The cause of the problem is worn or bent suspension components. Replace as necessary. Have you replaced the parts? | -- | System OK | -- |
