
Fleece Performance Engineering FPE-CUMM-SSHCL-12V Replacement Heater Core Line Kit (1989-1998 5.9L Cummins)
Diesel Dollars is Southern Diesel Supply's Loyalty Program. Purchasing with Us Earns you 1 Point for every 1 Dollar spent to use for future buys!
By ordering the Fleece Performance Engineering FPE-CUMM-SSHCL-12V Replacement Heater Core Line Kit (1989-1998 5.9L Cummins) you will earn 398 DIESEL DOLLARS in your SDS Fuel Tank!
Replace your leaking or corroded heater tubes with our upgraded stainless steel tubes and high temperature silicone hose kit from Fleece Performance Engineering. This kit contains everything you need to replace your heater lines from the block to the firewall.
This kit is designed as a direct replacement for all trucks originally equipped with air conditioning.
Kit includes:
- Stainless steel heater tube - replaces Cummins 3912086
- Stainless steel heater tube - replaces Cummins 3912087
- Silicone heater hose (straight tube to block) - replaces Cummins 3931522
- Silicone heater hose (90 deg tube to block) - replaces Cummins 3957649
- Silicone heater hoses (45 deg tubes to firewall)
- Anodized billet aluminum hold down clamps, billet aluminum standoff, and mounting hardware for both stock and aftermarket manifolds
- Hose clamps
Application Notes:
This kit is intended for use with trucks originally equipped with air-conditioning. If your truck is not equipped with air conditioning, you will need to supply your own 5/8 inch ID hose to run from the firewall ports to the stainless steel heater lines.
The silicone heater hose (tube to firewall) may require trimming for certain applications or to accommodate modifications made previously to the engine.
If your truck is equipped with an aftermarket exhaust manifold, the rear heater line standoff will not be utilized and an additional mounting bracket is provided.

Diesel Dollars is Southern Diesel Supply's Loyalty Program. Purchasing with Us Earns you 1 Point for every 1 Dollar spent to use for future buys!
By ordering the Fleece Performance Engineering FPE-CUMM-SSHCL-12V Replacement Heater Core Line Kit (1989-1998 5.9L Cummins) you will earn 398 DIESEL DOLLARS in your SDS Fuel Tank!


