Split Coefficient Test

Conducted July 9, 2001

Test procedures and equipment:

Test was completed using a 1990 Kenworth M-400 tractor with an unmodified OEM brake system. Therefore, burnishing was not needed.
1984 Trailmobile 48' van trailer
An MSQR-5000^® installed at each axle
Front wheel spread: 89"; rear wheel spread: 99"
6 stops at 20 MPH (32 km) and 6 stops at 55 MPH (88 km) on wet/dry road surface
Stopping lane was 12' wide (3.66 meters)

Stops at 20 MPH (32 km)

Stopping Distance

Vehicle Stability at Stopping

from Vehicle Center

Stop 1

20' 5"

(6.22 m)

Front left to left border: 77" (195.58 cm)

Rear left to left border: 67" (170.18 cm)

Front right to right border: 79" (200.66 cm)

Rear right to right border: 65" (165.10 cm)

Stop 2

17' 11"

(5.46 m)

Front left to left border: 73" (185.42 cm)

Rear left to left border: 71" (180.34 cm)

Front right to right border: 78" (198.12 cm)

Rear right to right border: 66" (167.64 cm)

Stop 3

22' 8"

(6.93 m)

Front left to left border: 73" (185.42 cm)

Rear left to left border: 71" (180.34 cm)

Front right to right border: 80" (203.20 cm)

Rear right to right border: 64" (162.56 cm)

Stop 4

18' 6"

(5.64 m)

Front left to left border: 74" (187.96 cm)

Rear left to left border: 70" (177.80 cm)

Front right to right border: 78" (198.12 cm)

Rear right to right border: 66" (167.64 cm)

Stop 5

11' 10"

(3.60 m)

Panic Stop

Front left to left border: 74" (187.96 cm)

Rear left to left border: 70" (177.80 cm)

Front right to right border: 77" (195.58 cm)

Rear right to right border: 67" (170.18 cm)

Stop 6

23' 2"

(7.06 m)

Front left to left border: 73" (185.42 cm)

Rear left to left border: 71" (180.34 cm)

Front right to right border: 79" (200.66 cm)

Rear right to right border: 65" (165.10 cm)

Stops at 55 MPH (88 km)

Stopping Distance

Vehicle Stability at Stopping

from Vehicle Center

Stop 1
176'

(53.64 m)

Front left to left border: 70" (177.80 cm)

Rear left to left border: 74" (187.96 cm)

Front right to right border: 74" (187.96 cm)

Rear right to right border: 70" (177.80 cm)

Stop 2
181'

(55.17 m)

Front left to left border: 72" (182.88 cm)

Rear left to left border: 72" (182.88 cm)

Front right to right border: 71" (180.34 cm)

Rear right to right border: 73" (185.42 cm)

Stop 3
Panic stop

40 psi

118'

(35.96 m)

Front left to left border: 70" (177.80 cm)

Rear left to left border: 74" (187.96 cm)

Front right to right border: 81" (205.74 cm)

Rear right to right border: 63" (160.02 cm)

Stop 4
172'

(52.43 m)

Front left to left border: 72" (182.88 cm)

Rear left to left border: 72" (182.88 cm)

Front right to right border: 70" (177.80 cm)

Rear right to right border: 74" (187.96 cm)

Stop 5

234'

(71.32 m)

Front left to left border: 72" (182.88 cm)

Rear left to left border: 72" (182.88 cm)

Front right to right border: 69" (175.76 cm)

Rear right to right border: 75" (190.50 cm)

Stop 6
Panic stop

31 psi

225'

(68.58 m)

Front left to left border: 74" (187.96 cm)

Rear left to left border: 70" (177.80 cm)

Front right to right border: 78" (198.12 cm)

Rear right to right border: 66" (167.64 cm)

Engineer

Carl J. Perazzola

Registered Professional Engineer in the State of Georgia