Product Description
Interstate-McBee M-3802132 Piston Kit – .020" Over, Marine Bowl – 1989–1998 5.9L Cummins 12-Valve
Quality aftermarket piston kit for the 5.9L Cummins 12-valve (6BT). This version uses the marine-style combustion bowl and a .020" (0.50 mm) oversize to match a cylinder that has been bored/honed .020" over. Ideal for performance refreshes and marine-bowl conversions. Sold per cylinder.
- Marine bowl crown: Pairs well with “marine” injector nozzles for targeted combustion.
- .020" oversize: For blocks machined to +0.50 mm over standard bore.
- Interstate-McBee quality: OE-style materials and manufacturing for durability.
- Complete per-cylinder kit: Includes piston, rings, pin, and pin retainers.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3802132 |
| OEM Cross-Reference | Cummins 3802132 (piston kit reference) |
| Bowl Type | Marine-style combustion bowl |
| Size / Oversize | .020" over (+0.50 mm) |
| Sold As | Each (1 cylinder kit) |
| Full Engine Qty | 6 kits required for one 6BT engine |
| Includes | (1) piston, (1) ring set, (1) wrist pin, (2) pin retainers |
| Engine | 5.9L Cummins 12-valve (6BT) |
What’s Included
- (1) Piston – marine bowl, .020" over
- (1) Matched piston ring set
- (1) Wrist pin
- (2) Pin locks/retainers
Vehicle / Engine Fitment
Verify by engine serial number (ESN) whenever possible.
- Dodge Ram 2500/3500 with 5.9L Cummins 12-valve (6BT)
- Model Years: 1989–1998
- Other B-Series 6BT applications using a marine-bowl piston where oversize .020" is specified
Ordering Notes
- Quantity: Sold per cylinder. Order 6 for a complete engine set.
- Machine work required: This piston is for cylinders bored/honed to +0.50 mm (.020"). Confirm final bore size and piston-to-wall clearance with your machinist.
- Ring file-fit: Always check and set ring end-gaps to the builder’s spec.
Installation Tips
- Clean all ring grooves and verify ring orientation (top marks up).
- Measure piston protrusion and verify gasket/select shim selection as applicable.
- Oil the wrist pin and small-end bushing during assembly; torque rod bolts per Cummins spec.
- Follow the Cummins service manual for clearances and torque sequences.
Frequently Asked Questions
What injectors work with a marine-bowl piston?
These pistons are commonly paired with “marine” style nozzles. Tuning and nozzle choice should match your build goals.
Can I mix marine-bowl and stock-bowl pistons?
No. All six cylinders should use the same bowl design to maintain balanced combustion.
Is this compatible with 24-valve (1998.5–2002) engines?
No. This listing is for 12-valve 6BT applications only.
