Curb Height Measurement
The wheel alignment is to be checked and all alignment adjustments made with the vehicle at its required curb height specification.
Vehicle height is to be checked with the vehicle on a flat, level surface, preferably a vehicle alignment rack.
The tires are to be inflated to the recommended pressure.
All tires are to be the same size as standard equipment.
Vehicle height is checked with the fuel tank full of fuel and no passengers or luggage compartment load.
Prior to reading the curb height measurement, the front and rear of the vehicle must be jounced to settle the suspension. Induce jounce by pushing down on the center of the bumper (fascia), using care not to damage the vehicle, moving the vehicle up and down, gradually increasing the suspension travel with each stroke. Release the bumper at the bottom of each stroke, repeating this action several times. Perform this to both front and rear suspensions an equal amount of times.
Vehicle height is not adjustable. If the measurement is not within specifications, inspect the vehicle for bent or weak suspension components. Compare the parts tag on the suspect coil spring(s) to the parts book and the vehicle sales code, checking for a match. Once removed from the vehicle, compare the coil spring height to a correct new or known good coil spring. The heights should vary if the suspect spring is weak.
Measure curb height as follows:
- Jounce the vehicle.
- FRONT - Locate the cradle bolt head (1). The cradle bolt passes through the lower control arm.
- FRONT - On each side of the vehicle, measure and record the distance from the center of the tire (1) to the ground.
- FRONT - On each side of the vehicle, measure and record the distance from the cradle bolt head (2) to ground.
- FRONT - Subtract the cradle bolt height (2) from the center bolt height (1) to obtain the curb height value (3). Compare the curb height value (3) to the specifications listed in the following CURB HEIGHT SPECIFICATIONS chart.
- REAR - On each side of the vehicle, measure and record the distance from the center of the rear leaf spring attachment bolt (1) to ground.
- REAR - On each side of the vehicle, measure and record the distance (2) from the center of the rear tire to ground.
- REAR - Subtract the rear leaf spring attachment bolt height (1) from the center of the rear tire height (2) to obtain the curb height value (3). Compare the curb height value (3) to specifications listed in the following CURB HEIGHT SPECIFICATIONS chart. Maximum left-to-right differential is not to exceed 10 mm (0.39 in.).
- If curb height is found to be out of specification and there is no sign of excessive body damage, curb height can be changed by replacing the applicable spring with a spring offering a different check load.
| 1500 Cargo Van - with 229 cm (90 in.) Roof | 1500 Cargo Van - with 257 cm (101 in.) Roof | 2500 Cargo Van - with 345 cm (136 in.) wheelbase | 2500 Cargo Van - with 404 cm (159 in.) wheelbase | 2500 Window Van | 3500 Cargo Van - with overall length of 600 cm (236 in.) | 3500 Cargo Van - with overall length of 635 cm (250 in.) | 3500 Window Van | ||
|---|---|---|---|---|---|---|---|---|---|
| Center of Spindle to Front Cradle Attachment Bolt | Front | 117 mm (4.60 in.) | 117 mm (4.60 in.) | 115 mm (4.52 in.) | 119 mm (4.68 in.) | 119 mm (4.68 in.) | 119 mm (4.68 in) | 121 (4.76 in.) | 121 mm (4.76 in.) |
| Center of Spindle to Rear Leaf Spring Attachment Bolt | Rear | -10 mm (- 0.39 in.) | -10 mm (- 0.39 in.) | - 8 mm (- 0.31 in.) | -10 mm (- 0.39 in.) | -10 mm (- 0.39 in.) | -10 mm (- 0.39 in.) | - 8 mm (- 0.31 in.) | -11 mm(- 0.43 in.) |
| All curb height tolerances +/- 10 mm (0.39 in.) with full fuel tank. | |||||||||