SAE J3096™ APR2026 Cooling System Nonmetallic Caps and Filler Necks - Threaded Construction

This SAE Recommended Practice specifies requirements for nonmetallic threaded cooling system caps and compatible metallic or nonmetallic filler necks.

SAE J3096™ APR2026 defines requirements for cooling system caps made from plastic materials with threaded attachments, along with the corresponding geometry for plastic and metallic filler necks. It addresses sealing, thread compatibility, pressure relief, safe cap removal, pressure and safety markings, and functional details for automotive cooling systems. The document is intended primarily for passenger cars, trucks, buses, construction vehicles, and related motor vehicle equipment, with potential use in marine, industrial, and similar applications. This edition is a five-year review that supersedes SAE J3096 JAN2021 and includes figures covering pressure caps and plastic and metal filler neck configurations.

Application Scope: Passenger cars, multipurpose passenger vehicles, trucks, chassis cabs, buses, construction vehicles, marine and industrial applications, and related motor vehicle cooling systems.