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Motor Vehicle Safety Standards; Electronic Stability Control Systems for Heavy Vehicles


American Government

Motor Vehicle Safety Standards; Electronic Stability Control Systems for Heavy Vehicles

Heidi R. King
National Highway Traffic Safety Administration
30 October 2017


[Federal Register Volume 82, Number 208 (Monday, October 30, 2017)]
[Rules and Regulations]
[Pages 50089-50093]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-23531]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-2015-0056]
RIN 2127-AL78


Motor Vehicle Safety Standards; Electronic Stability Control 
Systems for Heavy Vehicles

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation.

ACTION: Final rule; response to petition for reconsideration.

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SUMMARY: This final rule addresses a petition for reconsideration of 
the final rule for FMVSS No. 136, Electronic stability control systems 
for heavy vehicles. The petitioner, Truck and Engine Manufacturers 
Association (EMA), requested that NHTSA amend the test conditions for 
the agency's performance test by allowing a larger lane width for long 
wheelbase truck tractors. After a careful technical review of the 
petition and the issues raised by the petitioner, the agency has 
decided to grant the petition because there is sufficient evidence to 
indicate that a larger lane width is needed for testing of long 
wheelbase truck tractors.

DATES: The effective date of this final rule is November 29, 2017.
    Petitions for reconsideration: Petitions for reconsideration of 
this final rule must be received not later than December 14, 2017.

ADDRESSES: Petitions for reconsideration of this final rule must refer 
to the docket and notice number set forth above and be submitted to the 
Administrator, National Highway Traffic Safety Administration, 1200 New 
Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: For technical issues, you may contact

[[Page 50090]]

Patrick Hallan, Office of Crash Avoidance Standards, by telephone at 
(202) 366-9146, and by fax at (202) 493-2990. For legal issues, you may 
contact David Jasinski, Office of the Chief Counsel, by telephone at 
(202) 366-2992, and by fax at (202) 366-3820. You may send mail to both 
of these officials at the National Highway Traffic Safety 
Administration, 1200 New Jersey Avenue SE., Washington, DC 20590.

SUPPLEMENTARY INFORMATION: 

I. FMVSS No. 136 and J-Turn Test Maneuver

    On June 23, 2015, NHTSA published a final rule establishing Federal 
Motor Vehicle Safety Standard (FMVSS) No. 136, Electronic stability 
control systems for heavy vehicles, requiring electronic stability 
control (ESC) systems on truck tractors and certain buses with a gross 
vehicle weight rating greater than 11,793 kilograms (26,000 pounds).\1\ 
ESC systems in truck tractors and large buses are designed to reduce 
untripped rollovers and mitigate severe understeer or oversteer 
conditions that lead to loss of control using automatic computer-
controlled braking and reducing engine torque output.
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    \1\ 80 FR 36049.
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    To test the performance of ESC systems, NHTSA included a 150-foot 
radius J-turn test maneuver. The test course for the test maneuver is 
shown in Figure 1. This maneuver involves accelerating to a constant 
speed on a straight stretch of high-friction track before entering into 
a 150-foot radius curve. After entering the curve, the driver attempts 
to maintain the lane. At a speed that is up to 1.3 times the lowest 
entrance speed at which the ESC system activates, but no less than 48.3 
km/h (30 mph), an ESC system must activate the vehicle's service brakes 
to slow the vehicle to 46.7 km/h (29 mph) within 3 seconds after 
entering the curve and 45.1 km/h (28 mph) within 4 seconds after 
entering the curve. The test vehicle must also remain within the lane.
[GRAPHIC] [TIFF OMITTED] TR30OC17.002

    For truck tractors, the lane width is 3.7 meters (12 feet) for both 
the straight section and the curved section of the course. However, 
after testing large buses, the agency determined that large buses 
require additional lane width on the curved section of the course 
because buses have longer wheelbases, which make it substantially more 
difficult to maintain a narrower lane within the curve. During testing 
of buses on a 3.7 meter (12 foot) width lane, the bus could not 
maintain the lane because of the geometry of the vehicle, not because 
of lack of stability. NHTSA determined that 4.3 meters (14 feet) was an 
appropriate lane width for testing large buses.
    As described in the final rule, the nature of the J-turn test 
provides two criteria for ensuring vehicle responsiveness: Maintaining 
the lane within the fixed radius curve and a minimum test speed. These 
criteria for vehicle responsiveness are needed because there is a 
possibility of a manufacturer designing a vehicle that

[[Page 50091]]

responds poorly to the operator's speed and steering inputs, which 
would mask the actual performance of the ESC system.
    The first responsiveness criterion is the requirement that the 
vehicle maintain the lane during at least six of eight runs in the roll 
stability performance test series or at least two of four runs in the 
engine torque reduction test. This requirement ensures that, during J-
turn test runs at increasing speeds, the ESC system activates before 
the vehicle becomes unstable. We allowed multiple test runs, instead of 
a single test run, to account for driver variability and possible 
driver error in conducting the maneuver. Absent driver error, we do not 
expect any vehicle equipped with a properly functioning ESC system to 
exceed the lane width during any of the tests using the J-turn 
maneuver.
    The other responsiveness criterion in the final rule is the minimum 
vehicle entry speed, which is 48 km/h (30 mph) for the roll performance 
test. The reason for this requirement is to discourage a manufacturer 
from designing a system that unnecessarily intervenes at very low 
speeds, thus artificially decreasing the speed at which the vehicle 
will enter the curve during the roll performance test.

II. EMA Petition

    On August 7, 2015, the Truck and Engine Manufacturers Association 
(EMA) submitted a petition to NHTSA, pursuant to 49 CFR 553.35, 
requesting that the agency reconsider its June 2015 final rule 
establishing FMVSS No. 136. EMA is a trade association representing 
manufacturers of commercial motor vehicles, including medium- and 
heavy-duty truck tractors. EMA's petition indicated that the 3.7 meter 
(12 foot) lane width used in the FMVSS No. 136 test procedure presents 
difficulty in successfully completing the J-turn test for a small 
subset of truck tractors to achieve certification. According to EMA, 
long wheelbase truck tractors, such as specialty tractors and severe 
service tractors, cannot navigate the curve of the test course for the 
J-turn test maneuver because the radius paths of the trucks are 
dimensionally too large. This physical limitation does not allow the 
rear wheels to stay inside the 12-foot-wide lane. The petitioner states 
that this issue only affects certain long wheelbase truck tractors, 
which make up about one percent of the annual sales of the new truck 
tractor market.
    EMA asserted that the curved section of the 12-foot-wide lane is 
too narrow, and therefore, it is impracticable for the testing of a 
long wheelbase truck tractor with a wheelbase equal to or greater than 
7112 millimeters (280 inches). EMA stated that it was challenging for 
the drivers of tractors with wheelbases larger than 280 inches to 
complete the maneuver in the 12-foot-wide lane, because there was not 
an adequate margin of physical space to account for test variability. 
EMA listed factors that contribute to the variability of its test 
results which included: (i) The length of the tractor's wheelbase, (ii) 
the experience level of the test driver, (iii) whether the maneuver is 
conducted in the clockwise or counter-clockwise direction, and (iv) 
other vehicle attributes such as steering system, suspensions, axles, 
and tires. EMA has shown that there are dimensional limitations for 
certain long wheelbase truck tractors to conduct the J-turn test 
maneuver within 12-foot-wide lane and a larger lane width is needed to 
adequately test the ESC systems.
    In support of the petition for reconsideration, on June 30, 2016, 
EMA submitted data from testing and computer simulations indicating 
that a lane width of 4.3 meters (14 feet) was necessary for these long 
wheelbase truck tractors. EMA tested three truck tractors with three 
test drivers of varying degrees of experience in conducting the J-turn 
maneuver in both directions (clockwise and counterclockwise). EMA also 
performed computer simulations on three example tractors to do a static 
analysis showing the clearance of the truck tractor within the lane. 
Based on engineering recommendations from all of the major heavy-duty 
tractor manufacturers using the results of the computer simulations and 
the vehicle testing, EMA requests that truck tractors with a wheelbase 
equal to or greater than 7112 mm (280 inches) be conducted on a J-turn 
test course with a lane width of 4.3 meters (14 feet).

III. Agency Decision

    Pursuant to the process established under 49 CFR 553.37, after 
carefully considering all aspects of the petition and its subsequent 
data submission, the agency has decided to grant the petition without 
further proceedings. EMA's vehicle testing and computer simulation data 
support its position that truck tractors with a wheelbase equal to or 
greater than 7112 millimeters (280 inches) should be conducted on a 
test course with a wider lane, and we believe the suggested width of 
4.3 meters (14 feet) is appropriate. The agency had made similar 
provisions for large buses by allowing a 14-foot-wide lane after first 
considering a 12-foot-wide lane.\2\ During bus testing, NHTSA observed 
a decrease in clearance between a vehicle and the lane boundaries as 
wheelbase length increases. EMA's submission further reinforces this 
work and applies it to truck tractors. NHTSA agrees that there are 
dimensional limitations for long wheelbase vehicles that potentially 
make it impractical to conduct the J-turn test maneuver within 12-foot-
wide lane, and a larger lane width is needed to adequately test the ESC 
systems.
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    \2\ See Stability Control System Test Track Research with a 2014 
Prevost X3-45 Passenger Motorcoach, Docket No. NHTSA-2012-0065-0063.
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    In order to ensure that the J-turn test maneuver tests the ESC 
system and not a test driver's ability to maintain a narrow lane, NHTSA 
will adopt EMA's suggested 4.3 meter (14 foot) lane width for testing 
longer wheelbase truck tractors. Despite the increased lane width 
requirement for these long wheelbase truck tractors, NHTSA is confident 
that the ESC systems in these long wheelbase truck tractors will be 
adequately tested for minimum performance using the J-turn test 
maneuver because the driver must maintain the lane within the same 
fixed radius curve and travel at the same minimum test speed as all 
other truck tractors.
    This change requires two clarifications. First, as with buses, the 
wider lane is used only in the curved section of the test course. The 
lane width of the straight section will remain 3.7 meters (12 feet). 
The dimensional considerations that require a wider lane width for long 
wheelbase vehicles do not apply to straight sections of the test 
course.
    Second, NHTSA is clarifying the definition of wheelbase by 
including the definition in the regulatory text. For two-axle vehicles, 
the wheelbase is generally clear--the distance between the center of 
the front axle and the center of the rear axle. Moreover, for typical 
6x4 truck tractors, which have tandem rear axles, we believe the 
definition of wheelbase is also clear--the distance between the center 
of the front axle and the center of the rear tandem axles. However, to 
clarify wheelbase for all vehicles, including those with liftable axles 
or tag axles, NHTSA is specifying that the wheelbase is the 
longitudinal distance between the center of the front axle and the 
center of the rear axle. For vehicles with tandem axles, the center of 
the axle is considered to be the midpoint between the centers of the 
most forward and most rearward of the tandem axles, measured with any 
liftable axles down.

[[Page 50092]]

This definition is designed to directly reflect the geometrical 
concerns raised in the petition. Because all testing is done with any 
liftable axles in the lowered position, the wheelbase will be measured 
with liftable axles down so the wheelbase measurement accurately 
reflects the turning radius of the truck tractor. The term ``tandem 
axle'' is defined as it is in FMVSS Nos. 105 and 121 as a group or set 
of two or more axles placed in close arrangement, one behind the other, 
with the centerlines of adjacent axles not more than 72 inches apart.

IV. Rulemaking Analyses and Notices

A. Executive Order 12866, Executive Order 13563, and DOT Regulatory 
Policies and Procedures

    The agency has considered the impact of this rulemaking action 
under Executive Orders 12866 and 13563 and the DOT's regulatory 
policies and procedures. This action was not reviewed by the Office of 
Management and Budget under Executive Order 12866. The agency has 
considered the impact of this action under the Department of 
Transportation's regulatory policies and procedures (44 FR 11034; 
February 26, 1979), and has determined that it is not ``significant'' 
under them.
    This action addresses a petition for reconsideration of the June 
2015 final rule requiring ESC on truck tractors and certain large 
buses. However, the petition only addresses one test condition 
applicable to approximately one percent of truck tractors. This final 
rule amends the standard to allow long wheelbase truck tractors to be 
tested in a wider lane to account for the geometry of a turning vehicle 
and to ensure that the J-turn remains a test of the vehicle's stability 
and not the test driver. This final rule imposes no costs and adjusts 
FMVSS No. 136 to give more flexibility to manufacturers testing long 
wheelbase trucks. This action will not have any safety impacts.

B. Executive Order 13771

    Executive Order 13771 titled ``Reducing Regulation and Controlling 
Regulatory Costs,'' directs that, unless prohibited by law, whenever an 
executive department or agency publicly proposes for notice and comment 
or otherwise promulgates a new regulation, it shall identify at least 
two existing regulations to be repealed. In addition, any new 
incremental costs associated with new regulations shall, to the extent 
permitted by law, be offset by the elimination of existing costs. Only 
those rules deemed significant under section 3(f) of Executive Order 
12866, ``Regulatory Planning and Review,'' are subject to these 
requirements. As discussed above, this rule is not a significant rule 
under Executive Order 12866 and, accordingly, is not subject to the 
offset requirements of Executive Order 13771.
    NHTSA has determined that this rulemaking is a deregulatory action 
under Executive Order 13771, as it imposes no costs and, instead, 
amends FMVSS No. 136 to give more flexibility to manufacturers of long 
wheelbase truck tractors by allowing a wider lane in the test course. 
Although NHTSA was not able to quantify any cost savings for this rule, 
in adopting an optional wider lane width for the testing of long 
wheelbase truck tractors, this final rule adjusts the standard to 
accommodate the larger physical size of certain truck tractors and 
improves the efficiency of testing. This issue only affects long 
wheelbase truck tractors, which make up about one percent of the annual 
sales of truck tractors. The optional wider lane width will remove the 
difficulties cited by the petitioner associated with navigating the 
test course for long wheelbase truck tractors under the current test 
conditions in the standard.

C. Regulatory Flexibility Act

    Pursuant to the Regulatory Flexibility Act (5 U.S.C. 601 et seq., 
as amended by the Small Business Regulatory Enforcement Fairness Act 
(SBREFA) of 1996), whenever an agency is required to publish a notice 
of rulemaking for any proposed or final rule, it must prepare and make 
available for public comment a regulatory flexibility analysis that 
describes the effect of the rule on small entities (i.e., small 
businesses, small organizations, and small governmental jurisdictions). 
The Small Business Administration's regulations at 13 CFR part 121 
define a small business, in part, as a business entity ``which operates 
primarily within the United States.'' (13 CFR 121.105(a)). No 
regulatory flexibility analysis is required if the head of an agency 
certifies the rule will not have a significant economic impact on a 
substantial number of small entities. SBREFA amended the Regulatory 
Flexibility Act to require Federal agencies to provide a statement of 
the factual basis for certifying that a rule will not have a 
significant economic impact on a substantial number of small entities.
    NHTSA has considered the effects of this final rule under the 
Regulatory Flexibility Act. I certify that this final rule will not 
have a significant economic impact on a substantial number of small 
entities. NHTSA does not believe that any truck tractor manufacturers 
affected by this rule qualify as small entities. To the extent any 
business entities affected by this final rule do qualify as small 
entities, this final rule will not have a significant economic impact. 
This final rule addresses one test condition applicable to only one 
percent of truck tractors. This action will not result in added 
expenses for those manufacturers.

D. Privacy Act

    Anyone is able to search the electronic form of all documents 
received into any of our dockets by the name of the individual 
submitting the document (or signing the document, if submitted on 
behalf of an association, business, labor union, etc.). You may review 
DOT's complete Privacy Act Statement in the Federal Register published 
on April 11, 2000 (65 FR 19477-78) or you may visit http://www.transportation.gov/privacy.

E. Other Rulemaking Analyses and Notices

    In the June 2015 final rule, the agency discussed relevant 
requirements related to Executive Order 13132 (Federalism), Executive 
Order 12988 (Civil Justice Reform); Executive Order 13045 (Protection 
of Children from Environmental Health and Safety Risks); the Paperwork 
Reduction Act, the National Technology Transfer and Advancement Act, 
the Unfunded Mandates Reform Act, and the National Environmental Policy 
Act. As today's final rule merely adjusts one test condition in FMVSS 
No. 136 for approximately one percent of truck tractors subject to the 
standard, it will not have any effect on the agency's analyses in those 
areas.

List of Subjects in 49 CFR Parts 571

    Imports, Incorporation by reference, Motor vehicle safety, 
Reporting and recordkeeping requirements, Tires.

    In consideration of the foregoing, NHTSA amends 49 CFR part 571 as 
follows:

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

0
1. The authority citation for part 571 continues to read as follows:

    Authority:  49 U.S.C. 322, 30111, 30115, 30117, and 30166; 
delegation of authority at 49 CFR 1.95.


0
2. In Sec.  571.136, amend S4 by adding in alphabetical order the 
definitions of ``tandem axle'' and ``wheelbase'' and by revising 
S6.2.4.2 to read as follows:

[[Page 50093]]

Sec.  571.136  Standard No. 136; Electronic stability control systems 
for heavy vehicles.

* * * * *
    S4 Definitions.
* * * * *
    Tandem axle means a group or set of two or more axles placed in 
close arrangement, one behind the other, with the centerlines of 
adjacent axles not more than 72 inches apart.
* * * * *
    Wheelbase means the longitudinal distance between the center of the 
front axle and the center of the rear axle. For vehicles with tandem 
axles, the center of the axle is the midpoint between the centers of 
the most forward and most rearward tandem axles, measured when all 
liftable axles are in the lowered position.
* * * * *
    S6.2.4.2 For truck tractors, the lane width of the test course is 
3.7 meters (12 feet). At the manufacturer's option, for truck tractors 
with a wheelbase equal to or greater than 7112 mm (280 inches) the lane 
width of the test course is 3.7 meters (12 feet) for the straight 
section and is 4.3 meters (14 feet) for the curved section. For buses, 
the lane width of the test course is 3.7 meters (12 feet) for the 
straight section and is 4.3 meters (14 feet) for the curved section.
* * * * *

    Issued on October 20, 2017 in Washington, DC, under authority 
delegated in 49 CFR 1.95 and 501.5.
Heidi R. King,
Deputy Administrator.
[FR Doc. 2017-23531 Filed 10-27-17; 8:45 am]
 BILLING CODE 4910-59-P




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