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Trim Height Inspection



Trim Height Inspection

Trim Height Measurement

Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights can cause the vehicle to bottom out over bumps, damage to the suspension components and symptoms similar to wheel alignment problems. Check the trim heights when diagnosing suspension concerns and before checking the wheel alignment.

Perform the following before measuring the trim heights:

* Set the tire pressure to the specifications shown on the certification label. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label.
* Check the fuel level. Add additional weight if necessary to simulate a full tank.
* Make sure the passenger and rear compartments are empty, except for the spare tire.
* Make sure the vehicle is on a flat and level surface, such as an alignment rack.
* Check that all the vehicle doors are securely closed.
* Check that the vehicle hood and rear deck lids are securely closed.
* Check for installed after market accessories or modifications that could affect trim height measurement.

Important: All dimensions are measured vertical to the ground. Trim height should be within ±10 mm (±0.39 in) to be considered correct.

Measuring the P and R Dimension

Measuring The P And R Dimension:





Use the following procedure to check the P and R dimensions.

1. Use your hands to lift the front bumper approximately 38 mm (1.59 in).
2. Remove your hands and allow the vehicle to lower.
3. Use your hands to jounce the front of the vehicle downward approximately 38 mm (1.59 in).
4. Remove your hands and allow the vehicle to rise.
5. The dimension (P) for the left and right side of the vehicle is measured from the bottom lip of the wheel opening to the ground measured at the center line of the front wheel.
6. Compare the measurement to the specification table. Refer to Trim Height Specifications.
7. If the measurement is outside of the specified range, replace the front springs. Refer to Strut, Strut Component, and Spring Replacement.
8. Use your hands to lift the Rear bumper approximately 38 mm (1.59 in).
9. Remove your hands and allow the vehicle to lower.
10. Use your hands to jounce the rear of the vehicle downward approximately 38 mm (1.59 in).
11. The dimension (R) for the left and right side of the vehicle is measured from the bottom lip of the wheel opening to the ground measured at the center line of the rear wheel.
12. Compare the measurement to the specification table. Refer to Trim Height Specifications.
13. If the measurement is outside of the specified range, replace the rear springs. Refer to Coil Spring Replacement.

Measuring the Z Dimension

Measuring the Z Dimension:





The Z height dimension measurement determines the proper ride height for the front end of the vehicle. There is no adjustment procedure. Repair may require replacement of suspension components.

Use the following procedure to check the Z height dimension:

1. Use your hands to lift the front bumper approximately 38 mm (1.59 in).
2. Remove your hands and allow the vehicle to lower.
3. Use your hands to jounce the front of the vehicle downward approximately 38 mm (1.59 in).
4. Remove your hands and allow the vehicle to rise.
5. Repeat this operation a total of 3 times.
6. Measure from the bottom surface of the cradle, in line with the ball joint, to the bottom of the ball joint in order to obtain the Z height measurement.
7. Repeat the jouncing operation 2 more times.
8. Measure the Z height dimension again.
9. The true Z height dimension number is the average of the high and the low measurements.
10. Compare the measurement to the specification table. Refer to Trim Height Specifications.
11. If these measurements are out of specifications, inspect for the following conditions:
* Worn or damaged suspension components
* Collision damage

D Height Measurement

D Height Measurement:





The D height dimension measurement determines the proper rear end ride height. There is no adjustment procedure. Repair may require replacement of suspension components.

Use the following procedure to check the D dimension:

1. Use your hands to lift the rear bumper approximately 38 mm (1.59 in).
2. Remove your hands and allow the vehicle to lower.
3. Use your hands to jounce the rear of the vehicle downward approximately 38 mm (1.59 in).
4. Remove your hands and allow the vehicle to rise.
5. Repeat this operation a total of 3 times.
6. Measure the vertical distance between the bottom edge of the upper spring seat to the bottom of the notch in the lower spring seat. This measurement is the D height.
7. Compare the measurement to the specification table. Refer to Trim Height Specifications.
8. If these measurements are out of specifications, inspect for the following conditions:
* Worn or damaged suspension components
* Collision damage