Product Description
Cummins 4089650 — Upper Engine Gasket Kit (.010 Oversize / 0.25 mm)
MPN: 4089650 | Also Known As: top-end gasket set, upper gasket set | Includes: +.010" (0.25 mm) head gasket for resurfaced deck/head
Why This Part
- ✓ OE-spec upper set for complete top-end reseal on 5.9L 12-valve 6BT.
- ✓ +.010" (0.25 mm) head gasket to restore compression after decking.
- ✓ Direct-fit components for factory sealing surfaces.
- ✓ Helps prevent coolant/oil cross-leaks and restores reliability.
Quick Specs
| Type | Upper engine gasket kit (top-end set) |
|---|---|
| OE Part # | 4089650 |
| Head Gasket | +.010" / 0.25 mm oversize (e.g., 3283337) |
| Qty Required | 1 per engine (sold as a set) |
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1989–1998 | 5.9L Cummins 6BT (12-Valve) | Ram 2500/3500 |
Industrial/Off-Highway: 6B/6BT applications also use this kit; verify by ESN. Note this is the +.010" (0.25 mm) thickness kit intended for resurfaced heads/blocks.
Often Paired With
- Head bolts or studs (recommended when doing head gasket work)
- Coolant, oil & filter for post-install service
- Intake/exhaust fasteners if originals are corroded
What’s In The Box
- Upper engine gasket set featuring +.010" (0.25 mm) head gasket (e.g., 3283337) and associated top-end seals/gaskets (intake, exhaust, injector washers, valve cover, thermostat housing, etc.). Contents may vary by ESN.
Install Tips
- Clean and inspect all mating surfaces; check flatness against spec.
- Follow factory torque sequence and angle; use fresh fasteners as required.
- Re-fill fluids, bleed air, and recheck for leaks after heat cycle.
FAQ
IS THIS THE +.010" (0.25 mm) THICKNESS KIT?Yes—4089650 includes the +.010" oversize head gasket for engines with resurfaced deck and/or cylinder head.
WHAT TRUCKS DOES THIS FIT?It’s targeted to 1989–1998 Ram 2500/3500 with the 5.9L 12-valve 6BT. Always confirm by ESN.
WHAT’S THE DIFFERENCE VS. STANDARD THICKNESS KITS?Standard kits use a stock-thickness head gasket; 4089650 compensates +.010" for material removed during machining. If you need standard thickness, see OE kits like 4090035 (verify by ESN).
IS THIS A GENUINE CUMMINS UPPER SET?Yes—4089650 is the OE upper engine gasket kit part number.
WHAT IF MY ENGINE IS INDUSTRIAL OR NON-CERT B-SERIES?This kit is used primarily on 5.9L B-series (including Non-Certified) applications. Confirm by ESN for exact contents.
