Product Description
Interstate-McBee M-3802134 Piston Kit – .040" Oversize, Marine Bowl – 1989–1998 5.9L Cummins 12-Valve
Quality aftermarket piston kit engineered for the 1989–1998 5.9L Cummins 12-valve (6BT). This version features a .040" oversize (+1.00 mm) with a marine-style combustion bowl. Ideal for rebuilds that require an overbore and a durable piston profile. Sold per cylinder (one kit per hole).
- Precision oversize: .040" (+1.00 mm) for blocks that are bored/honed beyond standard.
- Marine bowl design: Robust bowl geometry suitable for heavy-duty use.
- Complete kit: Includes piston, ring set, wrist pin, and pin retainers/locks.
- Interstate-McBee quality: OE-equivalent fit and performance.
What’s Included
- (1) Piston – .040" oversize (+1.00 mm)
- (1) Piston ring set (matched to piston size)
- (1) Wrist pin
- (2) Pin retainers/locks
Vehicle Fitment
Always verify by engine serial number (ESN) and required oversize.
- Cummins 6BT 5.9L 12-valve (1989–1998 Dodge Ram 2500/3500 and industrial/ag/marine 6BT where 3802134 is specified)
- Does not fit 24-valve (1998.5–2002) engines
Install Notes
- Machine work required: Block must be bored and honed to the correct finish for .040" oversize. Measure every cylinder.
- Verify piston-to-wall clearance, ring end-gaps, and deck/protrusion per the Cummins service manual.
- Cleanliness matters: Thoroughly wash bores after honing; use clean engine oil or specified assembly lube on rings and pins.
- Orient rings per instructions; confirm ring markings (TOP) and gap positions.
- Check combustion bowl orientation if applicable to your application.
Recommended/Related Parts
- Full gasket set (upper/lower) for 5.9L 12-valve
- Main and rod bearing sets (select sizes as required)
- Piston cooling nozzles/jets (inspect/replace if worn or damaged)
- Head bolts or studs, oil pump, timing set components as needed
FAQ
How many kits do I need?
Order six (6) kits for a complete 6-cylinder rebuild.
What does .040" oversize mean?
The cylinder bores are enlarged by approximately .040" (+1.00 mm) during machining. Rings and pistons are matched to that size.
Is this a direct drop-in?
No. Proper machine work, measurements, and assembly procedures are required. Always follow the Cummins service manual.
Specifications for Interstate-McBee M-3802134
| Brand | Interstate-McBee |
| Part Number | M-3802134 |
| UPC | Not specified by manufacturer/seller |
| GTIN | Not specified by manufacturer/seller |
| Shipping Info | Approximate package weight: 10 lb (4.54 kg). Additional shipping dimensions/method: Not specified; ships via standard small-parcel service. |
| Cross Reference | Primary OEM reference: Cummins 3802134 piston kit (.040" / 1.00 mm oversize, marine bowl). Additional interchange numbers reported by distributors include: IF38021344B, OH38021344B, 3802134, and other catalog listings that map Cummins 3802134 to Interstate-McBee M-3802134. |
| E-Codes | Not specified |
| Prop 65 | WARNING: This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information: https://www.P65Warnings.ca.gov |
