Table 4-34: Federal Exhaust Emission Certification Standards for Newly Manufactured Gasoline- and Diesel-Powered Light-Duty Trucks (Category LDT4)

(Grams per mile)

Engine type and pollutant Prior to controlg 1968-1969 1970-1971 1972 1973-1974 1975 1976-1978 1979-1981 1982-1983 1984 1985-1986 1987 1988-1989 1990 1991-1995 Tier 1k 1996-2007 Interim Tier 2k 2008 Tier 2k 2009+
Gasoline
HC (total) 11 I 2.2 3.4 3.4 2.0 2.0 1.7 1.7 0.80 0.80 0.80 0.80 0.80 0.80 j (0.8) j j
NMHC h j j j j j j j j j j j j j j 0.39 (0.56) j j
NMOG h j j j j j j j j j j j j j j j 0.160 (0.230) 0.125 (0.156)
CO 80 i 23 39 39 20 20 18 18 10 10 10 10 10 10 5 (7.3) 4.4 (6.4) 3.4 (4.2)
Cold-temp. COd h j j j j j j j j j j j j j j 12.5 (j) 12.5 (j) 12.5 (j)
NOx 4 j j j 3.0 3.1 3.1 2.3 2.3 2.3 2.3 2.3 2.3 1.7 1.7 1.1 (1.53) 0.4 (0.6) 0.14 (0.20)
Particulates h j j j j j j j j j j j j j j j (0.12) 0.08 (0.08) 0.02 (0.02)
Formaldehyde h j j j j j j j j j j j j j j j 0.018 (0.027) 0.015 (0.018)
Diesel
HC (total) 11 j j j j j 2.0 1.7 1.7 0.80 0.80 0.80 0.80 0.80 0.80 j (0.8) j j
NMHC h j j j j j j j j j j j j j j 0.39 (0.56) j j
NMOG h j j j j j j j j j j j j j j j j (0.230) 0.125 (0.156)
CO 80 j j j j j 20 18 18 10 10 10 10 10 10 5 (7.3) j (6.4) 3.4 (4.2)
NOx 4 j j j j j 3.1 2.3 2.3 2.3 2.3 2.3 2.3 1.7 1.7 j (1.53) j (0.6) 0.14 (0.20)
Particulates h j j j j j j j 0.60 0.60 0.60 0.50 0.45 0.45 0.13 j (0.12) j (0.08) 0.02 (0.02)
Formaldehyde h j j j j j j j j j j j j j j j j (0.027) 0.015 (0.018)
LDT4 weight criteriae   GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds Any ALVW Any ALVW Any ALVW ALVW over 5,750 pounds ALVW over 5,750 pounds ALVW over 5,750 pounds
LDT4 weight criteriae   GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 6,000 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR up through 8,500 pounds GVWR 6,001-8,500 pounds GVWR 6,001-8,500 pounds GVWR 6,001-8,500 pounds GVWR 6,001-8,500 pounds GVWR 6,001-8,500 pounds GVWR 6,001-8,500 pounds
Test procedureb   7-mode 7-mode CVS-72 CVS-73 CVS-75 CVS-76 CVS-77 CVS-78 CVS-79 CVS-80 CVS-81 CVS-82 CVS-83 CVS-84 CVS-85 CVS-86 CVS-87
Useful life, intermediatec,f   j j j j j j j j j j j j j j 5 years/50,000 miles 6 years/50,000 miles 7 years/50,000 miles
Useful life, full   5 years/50,000 miles 6 years/50,000 miles 7 years/50,000 miles 8 years/50,000 miles 9 years/50,000 miles 10 years/50,000 miles 11 years/50,000 miles 12 years/50,000 miles 13 years/50,000 miles 11 years/120,000 miles 12 years/120,000 miles 13 years/120,000 miles 14 years/120,000 miles 15 years/120,000 miles 16 years/120,000 miles 17 years/120,000 miles 18 years/120,000 miles

vehicle weight rating; HC = hydrocarbons; NMHC=nonmethane hydrocarbon; NMOG=nonmethane
organic gases; NOx=nitrogen oxides.

a Light-duty truck categories LDT1-LDT4 were not created until 1994.
From 1968 to 1978 all trucks with a GVWR up to 6,000 pounds were classified
as light-duty trucks and were required to meet the same standards. As of 1979,
the maximum weight was raised to 8,500 pounds GVWR. During 1988-93, light-duty
trucks were divided into two subcategories that coincide with the current LDT1-LDT4
categories. The standards for LDT1, LDT2, and LDT3 are given in tables 4-30a,
4-40b, and 4-30c.

b The test procedure for measuring exhaust emissions has changed
several times over the course of vehicle emissions regulation. The 7-mode procedure
was used through model year 1971 and was replaced by the CVS-72 procedure beginning
in model year 1972. The CVS-75 procedure became the test procedure as of model
year 1975. While it may appear that the total HC and CO standards were relaxed
in 1972-74, these standards were actually more stringent due to the more stringent
nature of the CVS-72 test procedure.

Additional standards for CO and composite standards for NMHC and NOx tested
over the new Supplemental Federal Test Procedure will be phased-in beginning
with model year 2002. These standards are not shown in this table.

c Emissions standards had to be met for a full useful life of 5
years/50,000 miles through model year 1983, and a full useful life of 11 years/120,000
miles was defined for 1985-93 (several useful life options were available for
1984). Beginning in model year 1996, emissions standards were established for
an intermediate useful life of 5 years/50,000 miles as well as a full useful
life of 11 years/120,000 miles (intermediate and full useful life standards
are shown in parentheses). This applied to all pollutants except HC and particulates
for all LDT4 vehicles and NOx for diesel-powered LDT4 vehicles, which were only
required to meet full useful life standards. Tier 1 exhaust standards were phased-in
during 1996-97 at a rate of 50% and 100%, respectively.

d The cold CO emissions standard is measured at 20 0F
(rather than 75 0F) and is applicable for a 5-year/50,000-mile useful
life.

e GVWR is the maximum design loaded weight. ALVW is the numerical
average of the GVWR and the curb weight.

f Manufacturers can opt to certify vehicles for a full useful life
of 15 years/150,000 miles and either have (1) intermediate useful life standards

g The "Prior to control" column reports emissions estimates
of a typical newly manufactured car in the years before exhaust emissions certification
standards were implemented.

h No estimate available.

i In 1968-69, exhaust emissions standards were issued in parts per
million rather than grams per mile and are, therefore, incompatible with this
table.

j No standard has been set.

k The term "tier" refers to a level of standards for specific
years. Interim 2 refers to an intermediate level of standards that moves manufacturers
toward compliance with Tier 2 standards. Interim Tier 2 and Tier 2 standards
are established as "bins." Each bin is a set of standards for NOx,
CO, NMOG, formaldehyde, and particulate matter (HC and non-methane HC standards
are dropped for Tier 2 and interim Tier 2). Manufacturers may certify any given
vehicle family to any of the bins available for that vehicle class as long as
the resulting sales-weighted corporate average NOx standard is met for full
useful life. The Tier 2 corporate average NOx standard is 0.07 grams/mile. Interim
corporate-based average NOx standards are based on vehicle type. The interim
corporate sales-weighted average for LDT4 vehicles is 0.6 grams/mile. Tier 2
standards will be phased in during 2008 and 2009. In 2008, 50% of LDT4 vehicles
must meet Tier 2 standards; the others must meet Interim Tier 2 standards. Beginning
in 2009, all LDT4 vehicles must meet Tier 2 standards.

SOURCES

40 CFR 86, Subpart A (July 1, 2000).

Federal Register, Vol. 65, No. 28, pp. 6851-6858.

Updated: Sunday, May 21, 2017