D Height Measurement
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The D height dimension measurement determines the proper ride height for the rear end of the vehicle. There is no adjustment procedure. Repair may require replacement of suspension components.
Important: All dimensions are measured vertical to ground. Cross vehicle D heights should be within 10 mm (0.39 in) to be considered correct.
- Place hand on the rear bumper and jounce the rear of the vehicle. Make sure that there is at least 38 mm (1.5 in) of movement while jouncing.
- With the vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 in).
- Allow the vehicle to settle into position.
Important: Measure the metal to metal contact points of the rear axle to the frame on the inboard side of the leaf springs.
- Measure the D height by measuring the distance between the bumper bracket and the top of the rear axle tube.
- Repeat the jouncing operation 2 more times for a total of 3 times.
- Use the highest and lowest measurements to calculate the average height.
- The true D height dimension number is the average of the highest and the lowest measurements. Refer to TRIM HEIGHT SPECIFICATIONS
- If these measurements are out of specifications, inspect for the following conditions:
- Sagging front suspension Refer to TORSION BAR REPLACEMENT in FRONT SUSPENSION SYSTEM .
- Sagging rear leaf/coil springs Refer to LEAF SPRING REPLACEMENT or COIL SPRING REPLACEMENT in REAR SUSPENSION SYSTEM .
- Worn rear suspension components, such as leaf spring bushings Refer to SPRING BUSHING REPLACEMENT in REAR SUSPENSION SYSTEM .
- Improper tire inflation.
- Improper weight distribution
- Collision damage