3965999 / 5361595 Cummins ISB 6.7L 24-Valve Loaded Cylinder Head – New, Stage 1
| Brand | JAK's Diesel |
| Part Category | Cylinder Heads |
| Engine Make | Cummins |
| Engine Model | ISB · ISB 6.7 · 6.7L CUMMINS |
| Condition | New |
| Stage / Tier | Stage 1 |
New, fully loaded cylinder head for the Cummins ISB 6.7L 24-valve, built to replace Cummins 3965999 and 5361595. Standard intake and exhaust valves for a straight stock-power replacement. It arrives assembled and ready to bolt on, with no core to send back.
What's Included
- New cylinder head casting
- New intake and exhaust valves (Stage 1 standard intake and exhaust)
- New valve springs, retainers and keepers
- Valve guides and valve stem seals installed
Not included: head gasket set, head bolts, injectors, rocker assemblies. Ask us and we will quote the matching gasket set and bolt kit.
Specifications
| Replaces | Cummins 3965999, 5361595 and cross-references below |
| Engine | Cummins ISB 6.7L 24-valve |
| Condition | New — no core |
| Assembly | Loaded (valves, springs, retainers, keepers, guides, seals) |
| Valve package | Stage 1 — standard intake and exhaust |
| Brand | JAK's Diesel |
Fitment
Fits Cummins ISB 6.7L 24-valve engines that use the 3965999 / 5361595 head. For later engines that call for 4983298, see our 2013+ ISB 6.7 head. We confirm fitment by engine serial number (ESN) or casting number before every head ships.
Replaces / Cross-Reference Part Numbers
OEM and reman numbers: 3965999, 3965998, 5361595, 3954673, 3957384, 3957385, 3957386, 3957408, 3957958, 3957959, 3958170, 3968185, 3968186, 3969071, 3977222, 3977225, 3977226, 3977227, 3977228, 4895759, 4895765, 4931564, 4931645, 4933955, 4936081, 4955212, 4981626, 4981627, 5270036, 5282703, 5282721
Shipping, Core & Warranty
- No core charge, no core return. This is a new casting, not an exchange unit.
- Freight: ships crated by LTL freight. Freight is free to a commercial address with a forklift or dock. Residential, liftgate and terminal delivery can be quoted — call before you order.
- Local pickup: available in Henderson, CO by arrangement.
- Warranty: 1 year against defects in materials and workmanship.
Frequently Asked Questions
Is this head new or remanufactured?
New. It is a new casting assembled with new valvetrain components — not a rebuilt core.
Do I have to send back a core?
No. There is no core charge and nothing to return.
What else do I need to install it?
Plan on a new head gasket set and head bolts for the ISB 6.7. They are not included. Message us and we will match the right kit to your engine serial number.
How do I confirm it fits my ISB 6.7?
Send us your engine serial number (ESN) or the casting number from your old head. We verify fitment against 3965999 before the head ships.
5.9 or 6.7 — how do I know which head I need?
Send us your engine serial number (ESN) or the casting number on your old head. ISB 5.9 and 6.7 heads look alike but are not all interchangeable.
How long does delivery take?
Heads are crated and handed to the LTL carrier in 1–2 business days. Transit is typically 2–5 business days depending on your location.
Questions? Call JAK's Diesel at (720) 445-6249. See all Cummins B-Series / ISB parts or diesel cylinder heads.
Discovery models are listed below. Confirm the complete application and any ESN/CPL or size restrictions before ordering.
