Bosch Fuel Injection Pump 0403436109 3915581 3915581RX for Cummins Engine 6CTA 8.3
This fuel pump is engineered as a direct replacement for the Cummins Engine 6CTA 8.3. Manufactured to meet or exceed OEM specifications, it delivers reliable performance in demanding conditions. Each unit is tested for fuel flow, pressure rating, and durability before leaving the factory to ensure consistent quality across every order.
Vehicle Compatibility
| Application | Details |
|---|---|
| Cummins Engine 6CTA8.3 6C8.3 Replacement Part Number:3915581RX, 3915581, 2910 | 01-268-8757, 2910012688757, 0-403-436-109, 0403436109, 0403436100, 0403436102, 3910722, 3910063 Fit For |
| Cummins Engine: 6CTA 8.3, 6C8.3 Applications:Fit for 5 Ton Military Truck: M939A2, M923A2, M925A2, M927A2, M929A2, M930A2, M931A2 | See product specifications |
Replaces OEM Part Numbers
3915581RX • 3915581 • 2910-01-268-8757 • 2910012688757 • 0-403-436-109 • 0403436109 • 0403436100 • 0403436102 • 3910722 • 3910063 • Cummins • Engine
Signs You Need a Replacement
If your equipment is showing any of these symptoms, the fuel pump may be the cause:
- Engine cranks but won’t start — The pump may have lost prime or stopped delivering fuel. Check for fuel at the filter outlet before replacing the pump.
- Stalling under load — A weak pump can’t maintain pressure at high demand. The engine runs fine at idle but dies when you put it to work.
- Fuel pressure warning (if equipped) — Modern Cummins equipment monitors fuel rail pressure. A low-pressure warning often means the pump is failing.
- Loud whining from fuel system — A failing pump makes a high-pitched whine that gets louder as it warms up. Normal pump noise is a low hum.
- Air in fuel lines — If you see bubbles in the transparent fuel line or the primer bulb won’t stay firm, the pump may be drawing air through a worn seal.
- Excessive return flow — Too much fuel returning to the tank instead of reaching the injectors indicates internal pump wear.
Before You Replace the Pump
Before replacing the pump, check the fuel filter and fuel lines for restrictions. A blocked filter causes the same symptoms as a failing pump on Cummins equipment. When installing the new pump, fill it with clean fuel before connecting the lines — this reduces priming time and prevents dry-run damage. After installation, bleed the system fully and check for leaks at all connection points. Replace the fuel filter at the same time as the pump to protect the new unit from debris.
Frequently Asked Questions
Which Cummins models does this part fit?
Refer to the Vehicle Compatibility table above for the full list of Cummins models. Each listing includes the body type, engine, and production years. Match your vehicle’s engine code (stamped on the engine block) against the listed codes to confirm.
Can I cross-reference 3915581RX with 3915581?
Yes. Both 3915581RX and 3915581 are interchangeable OEM numbers for this part. They refer to the same component with the same specifications, just different part number revisions.
I have a 8.3 engine – which version do I need?
This part covers 8.3 applications. To narrow down the exact fit, check your vehicle’s model year and engine code. The same displacement can have multiple engine variants with different fuel systems or emissions equipment.
How long does a Cummins fuel pump typically last?
Fuel pump life varies by application, but on Cummins equipment you can generally expect 5,000 to 10,000 hours of operation. Running the tank dry, using contaminated fuel, or neglecting the fuel filter are the top causes of premature failure.


Reviews
There are no reviews yet.