1. FMCSA 3 Year Heavy Vehicle Data Collection Effort

2. Heavy Vehicle Data Collection Effort
PURPOSE – To gather data to help determine what, if any, impact heavier weight have on a vehicle’s structural components, motor carrier safety violations, and safety.
DURATION – January 15, 2012 – January 15, 2015
A heavy vehicle was included in the study if:
It was weighed and found to be over the allowable:
Axle weight; and/or
Axle group weight; and/or
Gross vehicle weight for the roadway on which it is operating OR
It was operating under a special permit for weight

3. General Inspection Information
Timeframe
No. CMV Inspections
No. OOS
CMV OOS Rate
6 months
2,485
922
37.10%
1 year
5,109
1,830
35.82%
18 months
7,602
2,696
35.46%
2 years
9,541
3,494
36.62%
30 months
10,564
3,961
37.50%
3 years
11,352
4,281
37.71%

4. 3 Year Inspection Information
Combination CMV?
No. CMVs
OOS Rate
Yes
8,888
39.33% No
2,462
31.86%

5. General Inspection Information by Permit
Timeframe
Permitted CMV?
No. CMVs
OOS Rate
6 months
Yes
273
32.97% No
2,212
37.61%
1 year
435
33.79%
4,674
36.01%
18 months
558
35.30%
7,044
35.48%
2 years
632
35.44%
8,909
36.70%
30 months
682
36.36%
9,882
37.57%
3 years
723
36.65%
10,629
37.78%

6. Top Violation Types Violation No. CMVs 4,165 2,402 2,198 1,596 1,984
No. Occurrences
No. CMVs
Clamp/Roto type brakes out of adjustment
4,165
2,402
Inoperable required lamp
2,198
1,596
State/Local laws – Excessive weight: 1-2,500 lb over on an axle/axle groups
1,984
1,863
State/Local laws – Excessive weight: 2,501-5,000 lb over on an axle/axle groups
1,659
1,589
Inspection, repair and maintenance of parts and accessories
1,641
1,242
CMV MFG > 10/19/94 with automatic AB adjust system fails to compensate for wear
1,505
1,394
Brakes out of service: The number of defective brakes is equal to or greater than 20%
1,439
1,429
Brake hose/tubing chaffing and/or kinking
997
764
Brakes (general)
984
790
Tire – Tread depth less than 2/32 inch
975
729
No/discharged/unsecured fire extinguisher
940
928
Oil and/or grease leak
847
763
Local laws
915
592
Inoperative turn signal
812
652
Operating a CMV without proof of a periodic inspection
798
610
Inoperative/defective brakes
593
State vehicle registration or license plate
753
639
Brake connections with leacks/constrictions
584
519
State/Local laws – Excessive weight: 1-2,500 lb over allowable gross weight
580
573
Stop lamp
556
487

7. OOS Violations (All CMVs)
Category
No. CMVs
OOS Rate
Brakes
1,558
13.72%
Brake adjustment
947
8.34%
Tires
444
3.91%
Suspension 78
0.69%
Wheels 44
0.39%
Other
1,210
10.66%
Total
4,281
37.71%

8. Weight Violations Violation No. CMVs No. OOS OOS Rate 392.2-SLLEWA1
1,863
676
36.29%
392.2-SLLEWA2
1,589
642
40.40%
392.2-SLLEWA3
287
138
48.08%
392.2-SLLEWG1
573
218
38.05%
392.2-SLLEWG2
310
142
45.81%
392.2-SLLEWG3
474
267
56.33%
392.2W
346
149
43.06%
Total
5,010
2,005
40.02%

9. Tractor and Trailer Violations
Tractors
Trailers
Violation Category
No. Occurrences
Brakes out of adjustment
2,426
2,111
Brakes (other)
3,589
3,066
Coupling devices 70 39
Fuel systems 40 3
Frames 86
174
Lighting
1,888
1,505
Steering mechanism
289
Suspension 91
183
Tires
629
1,126
Wheels, studs, clamps, etc.
139
194
Load securement 36
409
Windshield
349
Exhaust discharge
154
Emergency equipment
610 4
Periodic inspection
233
240
All other vehicle defects
2,235
1,493

10. Conclusion 36 months of data A 3 year final report is in draft
Trucks with weight violations have high OOS rates – Over 40%
There is a high rate of OOS violations

11. Heavy and Overweight Vehicle Stopping Distance Testing
2012

12. State Maximums – 5 Axles Florida, Wyoming, and Michigan
Allow up to 122,000 lb
New York and New Jersey
Allow up to 126,000 lb
Massachusetts and Connecticut
Allow up to 128,000 lb
Mississippi
Allows more weight depending on axle spacing and route
Wisconsin
Allows up to 142,000 lb
92,000 lb
104,000 lb
96,000 lb
106,000 lb
Maximum allowable GVW
98,000 lb
108,000 lb
100,000 lb
112,000 lb
102,000 lb
116,000+ lb

13. Heavy and Overweight Brake Testing
Impact on brake performance with increasing load
Impact on brake performance with brake degradation on tractor and trailer (20%)

14. FY 2012 Testing 5 Axle tractor/semitrailer
Reduced Stopping Distance Tractor Test
New brakes, drums, and tires
FMVSS No. 121 burnish
20 mph; 60 mph
Best Effectiveness
20% brakes out on tractor
20% brakes out on trailer

15. 5 Axle Reduced Corrected CMV Stopping Distance Averages for 60 mph Panic Stops

16. 5 Axle Stopping Distance Testing: Tire Load Capacity for Loading Conditions
Load Condition (lb)
GVW
(lb)
Steer
Axle
(lb), Capacity
Drive Axle Group
Trailer Axle Group
Tire Capacity
- -
14,320
45,400
52,880
Control Trailer
55,860
13,340
38,020
93.2%
83.7%
60,000 Load
60,040
12,630
24,490
22,920
88.2%
53.9%
43.3%
80,000 Balanced Load
80,040
12,810
32,640
34,590
89.5%
71.9%
65.4%
80,000 Unbalanced Load
80,010
13,200
38,710
28,100
92.2%
85.3%
53.1%
91,000 Load
91,440
13,140
38,240
40,060
91.8%
84.2%
75.8%
97,000 Load
97,120
12,660
33,390
51,070
88.4%
73.5%
96.6%
106,000 Load
106,340
13,710
45,080
47,550
95.7%
99.3%
89.9%
116,000 Load
116,100
13,780
48,770
53,550
96.2%
107.4%*
101.3%*
*Due to load positioning in these configurations, an overload condition was created for the rating of the tires available for testing. This was noted and will be addressed in future testing.

17. FY 2013-14 Testing 6 Axle tractor/semitrailer
Reduced Stopping Distance Tractor Test
Re-ran with non-RSD brakes installed
New brakes, drums, and tires
FMVSS No. 121 burnish
20 mph; 60 mph
Best Effectiveness
2 brakes out on tractor; 3 brakes out on tractor
2 brakes out on trailer; 3 brakes out on trailer
Steer axle brakes out

18. State Maximums – 6 Axles Maximum allowable GVW
North Carolina, South Dakota, and Oregon
Allow up to 119,000 lb
Texas
Allows up to 117,000 lb
New Mexico
Allows up to 118,000 lb
Mississippi
Allows up to 123,000 lb
Georgia
Allows up to 125,000 lb
New York
Allows up to 126,000 lb
Florida and Utah
Allow up to 127,000 lb
Massachusetts
Allows up to 128,000 lb
Maine
Allows up to 134,000 lb
Wisconsin
Allows up to 142,000 lb
Nebraska
Allows up to 102,000 lb
South Carolina
Allows up to 107,000 lb
100, ,000 lb
116, ,000 lb
Maximum allowable GVW
109, ,000 lb
120,000 lb
112,000 lb
122,000+ lb
113, ,000 lb
132,000+ lb

19. 6 Axle Corrected CMV Stopping Distance Averages

20. Suggestions
State weight violations (393.2*) should be included in CSA scoring
Tow vehicles (i.e. tractors) should not be allowed brake violations – OOS
Permit vehicles should not be allowed brake violations – OOS
Vehicles should not be permitted beyond its stated GVWR

21. Vehicle Configuration OOS Rate w/ Weight Violations
Level 1 Inspections
Vehicle Configuration
No. Inspections
OOS Rate
No. Weight Violations
OOS Rate w/ Weight Violations
Single Trailer
2,951,001
26.30%
82,472
41.89%
Double Trailer
59,799
26.76%
1,813
47.66%
Triple Trailer
834
17.03% 48
52.08%
Total
3,011,634
84,333
42.02%

22. Questions? Luke Loy, Sr. Engineer
FMCSA Vehicle and Roadside Operations Division