Curb Height Measurement

WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

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 passenger or luggage compartment load.

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.

Fig 1: Front Curb Height Measurement (LD)

Courtesy of CHRYSLER GROUP, LLC

Front - On each side of the vehicle, measure the distance from the center of the rear lower control arm bolt (1) to the ground (2) Record the measurement . Next measure the distance from the spindle center (3) to the ground (4) Record the measurement.
Take the two measurements and subtract them to get the curb height specification.

Fig 2: Rear Curb Height Measurement (LD)
Courtesy of CHRYSLER GROUP, LLC
Rear - On each side of the vehicle, measure the distance from the center of the lower control arm forward bolt (2) to the ground (3) Record the measurement . Next measure the distance from the center of the rear wheel (1) to the ground (4) Record the measurement.
Subtract the control arm bolt to floor measurement from the wheel to floor measurement to calculate the ride height. (wheel - control arm = ride height).

CURB HEIGHT SPECIFICATIONS - FRONT

MODEL	FRONT
4X4 Without TRX	64 mm - 84 mm
4X4 Without TRX	2.5 in - 3.3 in
4X4 With TRX	45 mm - 65 mm
4X4 With TRX	1.77 in - 2.5 in
4X2 With TRX	35 mm - 55 mm
4X2 With TRX	1.37 in - 2.16 in
4X2 With 17" Wheels Without TRX	47 mm - 67 mm
4X2 With 17" Wheels Without TRX	1.85 in - 2.63 in
4X2 With 20 and 22" wheels	35 mm - 55 mm
4X2 With 20 and 22" wheels	1.37 in - 2.16 in
Air Suspension NRH (Normal Ride Height)	75 mm - 95 mm
Air Suspension NRH (Normal Ride Height)	2.95 in - 3.74 in
Air Suspension (Aero Mode)	102 mm - 122 mm
Air Suspension (Aero Mode)	4.01 in - 4.80 in

CURB HEIGHT SPECIFICATIONS - REAR, 120" WHEELBASE

MODEL	REAR
4X4 Without TRX	60 mm - 80 mm
4X4 Without TRX	2.36 in - 3.14 in
4X4 With TRX	48 mm - 68 mm
4X4 With TRX	1.88 in - 2.67 in
4X2 With TRX	72 mm - 92 mm
4X2 With TRX	2.83 in - 3.62 in
4X2 With 17" Wheels Without TRX	72 mm - 92 mm
4X2 With 17" Wheels Without TRX	2.83 in - 3.62 in
4X2 With 20 and 22" wheels	69 mm - 89 mm
4X2 With 20 and 22" wheels	2.71 in - 3.5 in

CURB HEIGHT SPECIFICATIONS - REAR, 140, 149" WHEELBASE

MODEL	REAR
4X4 Without TRX	58 mm - 78 mm
4X4 Without TRX	2.28 in - 3.07 in
4X4 With TRX	46 mm - 66 mm
4X4 With TRX	1.81 in - 2.59 in
4X2 With TRX	71 mm - 91 mm
4X2 With TRX	2.79 in - 2.8 in
4X2 With 17" Wheels Without TRX	71 mm - 91 mm
4X2 With 17" Wheels Without TRX	2 in - 3.58 in
4X2 With 20" wheels	69 mm - 89 mm
4X2 With 20" wheels	2.71 in - 3.5 in
Air Suspension NRH (Normal Ride Height)	69 mm - 89 mm
Air Suspension NRH (Normal Ride Height)	2.71 in - 3.5 in
Air Suspension (Aero Mode)	96 mm - 116 mm
Air Suspension (Aero Mode)	3.77 in - 4.56 in