ASI Performance Exhaust Manifold Fit Cummins 5.9L 6B ISB QSB B5.9 3943875 3942259 3943874

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SKU: 0538-50119A-1071

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$129.00

Size

Cummins 5.9L 6B ISB QSB B5.9

Fitment Notice: The fitment tool is for reference only. Please compare the dimensions, inlet/outlet sizes and positions, mounting points, and cooler connections with your original part before placing your order.

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U.S. Stock | Free Shipping (Excludes HI & AK)

1 Year Warranty

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This item ASI Performance Exhaust Manifold Fit Cummins 5.9L 6B ISB QSB B5.9 3943875 3942259 3943874

$129.00

ASI Performance Exhaust Manifold For Cummins 5.9L 6B ISB QSB B5.9 #3942225/3943872/3943871

$69.00

Package includes:

1x Exhaust Manifold

Application:

Fits For Cummins 5.9L 6B ISB QSB B5.9

Product Information:

Material: Cast Iron
Fitment: Direct Replacement
Part No.: 3943875 3942259 3943874

Description:

This exhaust manifold was precision-engineered and durably manufactured to match the fit and function of the original manifold on specified vehicles.
Ideal replacement - this exhaust manifold was precision-engineered and durably manufactured to match the fit and function of the stock manifold on specified vehicles
Reliable construction - durable materials resist warping, cracking and leaking for long-lasting performance

About ASI Performance

ASI Performance was founded in 2006, driven by a passion for engineering excellence and a commitment to high-performance cooling solutions for the automotive industry. Backed by an investment of over USD 1.5 million, we specialize in the development and manufacturing of radiators, intercoolers, silicone hoses, wheel spacer adapters, and related products for automotive, motorcycle, and ATV applications.

With a growing portfolio of over 3,000 products, ASI Performance continues to expand its range through constant innovation. More than 1,000 newly developed products, along with optimized upgrades of both modern and classic radiator models, have been successfully introduced to international markets worldwide.

As we continue to grow, our mission remains unchanged: to deliver reliable, performance-driven products and build long-term partnerships with customers around the world.

US Local Stock for Fast Delivery

We provide free shipping within the United States on all orders with no minimum spend. (Excludes remote areas such as Alaska and Hawaii. We are not able to deliver to Puerto Rico, Guam, or the Virgin Islands at this time.)

Estimated Shipping Time:

United States: 3-7 business days
We ship orders after payment is received. Once shipped, a tracking number will be generated and sent to your email.

Return Pollicy:

For returns or exchanges initiated due to product quality or delivery issues, asiproformance will cover the associated delivery charges.
However, if a return or exchange is requested due to the wrong size purchased or if the customer no longer wishes to keep the product, the customer will be responsible for covering the delivery charges incurred during the return or exchange process.

Warranty

Why choose us?

ASI Performance is a leading manufacturer of high-performance automotive components, including radiators, intercoolers, fitting & hoses, AC condensers and more. We design and manufacture our products in-house, controlling every step from material selection to final assembly to ensure precision and reliability. Each component undergoes strict quality inspections, including performance and durability tests, so you get products that meet or exceed industry standards. Our US local warehouse system ensures fast, secure shipping, with real-time tracking and careful packaging to prevent damage. On top of that, our responsive after-sales team provides professional guidance, troubleshooting, and warranty support, ensuring your investment is protected and your equipment performs at its best.

What is a radiator?

The radiator's job is to remove heat from the engine's coolant. As hot coolant passes through the radiator it is cooled before returning to the engine, where it absorbs heat and returns to the radiator. This cooling process keeps the engine from overheating.

How does the radiator work?

The engine generates heat when it is running; this heat must be removed to prevent damage to the engine. Coolant circulates throughout the engine and absorbs this heat. The water pump pushes the coolant through the radiator (where it is cooled) and returns it to the engine once more to absorb the engine’s heat, before returning it to the radiator to be cooled again. When a vehicle is traveling fast, rushing air flows through the radiator and cools the engine. When a vehicle is in stop-and-go traffic or stuck at a traffic light, the engine’s cooling fan pushes air through the radiator.

Can I drive with a radiator problem?

A sub-performing Radiator has far reaching effects. An inoperative heater, loss of coolant, or engine damage from overheating could occur. Overheating causes severe damage to an engine, including failure of the head gasket. Continuing to drive an overheating vehicle may disable the motor.

How often do radiators need to be replaced?

Replacement intervals vary greatly by vehicle and driving conditions. We typically see the radiator replaced at approximately 80,000 miles. While the radiator does not wear the same as a belt or brake pad, the repeated heating and cooling cycles the radiator experiences will eventually cause the degradation of its plastic end-tanks and seals.

How is a radiator replaced?

To replace the Radiator, the technician will drain the coolant from the cooling system and remove the Radiator and radiator hoses from the vehicle. This may also require removal of plastic shrouds and other engine bay cladding to reach the part. Where applicable, the cooling fan switch and electric cooling fan assemblies are transferred to the new Radiator. Once the new Radiator is installed, the cooling system is refilled with fresh coolant and the system is bled of any air, then rechecked to ensure all leaks have been fixed.