Upgrade your Cummins ISX DOHC in-frame overhaul to a true out-of-frame rebuild. The Big Boss Out-of-Frame Conversion Gasket Kit includes the critical front and rear structure gaskets and seals required when the engine is fully removed and rebuilt. Designed to pair seamlessly with PDI Big Boss In-Frame Kits, this set completes the engine structure for maximum sealing integrity, durability, and long-term reliability.

Built for professional rebuilders who won’t compromise when the engine is already out.

When You Need This Kit

This kit is required when a Cummins ISX DOHC engine is removed from the chassis and rebuilt as a full out-of-frame overhaul.

If your current rebuild plan includes separating the front structure or rear structure from the block, this kit supplies the necessary gaskets and seals that are not included in a standard in-frame overhaul kit.

Use this kit when:

• The engine is fully removed from the truck
• The front gear housing or rear housing is being resealed
• A standard in-frame kit is being upgraded to an out-of-frame