Allison 4000 series™ transmission now available with carb-compliant paccar mx-13 engine

New and only carb-compliant fully automatic transmission and diesel engine pairing to deliver lower emissions while maintaining optimized performance for heavy-duty vehicles indianapolis , july 30, 2025 /prnewswire/ -- allison transmission is pleased to announce the allison 4000 series™ fully automatic transmission is now available with the new carb low nox compliant paccar mx-13 engine for kenworth t880 and peterbilt model 567 truck models. the allison 4000 series™ is the only fully automatic transmission available with the mx-13 engine that is carb-compliant and the pairing is designed to optimize performance and reduce nox emissions.
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