Why Thousands Trust the Inline Upgrade
Top 10 Reasons Inline Beats Factory
Leak-proof alloy, emergency no-stat mode, easier bleeding, and more.
Watch the 2-Minute Explainer
Visual proof of why it runs cooler and never leaves you stranded.
40+ Pages of Real Owner Data
Temp logs, trail reports, and zero-drama installs from the D2 community.
Need Something Else?
Large Kits
Trucks & big SUVs
Medium Kits
Cars & light trucks
Adapter Kits
Universal & custom
Accessories
Hoses, thermostats, gaskets
Combine any order with ExtinctMotorsports.com for free shipping — click here to learn how