Manufacturers with annual U.S.-directed production volumes of greater than 20,000 tractors must perform testing as described in this section. Tractors may be new or used.

(a) The following test requirements apply for model years 2021 and later:

(1) Each calendar year, select for testing three sleeper cabs and two day cabs certified to Phase 1 or Phase 2 standards. If we do not identify certain vehicle configurations for your testing, select models that you project to be among your 12 highest-selling vehicle configurations for the given year.

(2) Set up the tractors on a chassis dynamometer and operate them over all applicable duty cycles from §1037.510(a). You may use emission-measurement systems meeting the specifications of 40 CFR part 1065, subpart J. Calculate coefficients for the road-load force equation as described in Section 10 of SAE J1263 or Section 11 of SAE J2263 (both incorporated by reference in §1037.810). Use standard payload. Measure emissions of NOX, PM, CO, NMHC, CO2, CH4, and N2O. Determine emission levels in g/hour for the idle test and g/ton-mile for other duty cycles.

(b) Send us an annual report with your test results for each duty cycle and the corresponding GEM results. Send the report by the next October 1 after the year we select the vehicles for testing, or a later date that we approve. We may make your test data publicly available.

(c) We may approve your request to perform alternative testing that will provide equivalent or better information compared to the specified testing. We may also direct you to do less testing than we specify in this section.

(d) GHG standards do not apply with respect to testing under this section. Note however that NTE standards apply for any qualifying operation that occurs during the testing in the same way that it would during any other in-use testing.