Mack Fuel Filter Mack MP8 engine | PN 21737481

You have 30 calendar days to return an item from the date you received it. To be eligible for return all parts must meet the following conditions:
• The item must be new, unused, and uninstalled;
• The product must be in salable condition, with no signs of installation (e.g., grease, scratches, or missing components);
• Original packaging is required, especially for branded parts;
• Any item that has been installed, modified, or misused is not eligible for return;
• Unacceptable returns may be shipped back to the customer upon request, at the customer's expense;
• Your item needs to have the receipt or proof of purchase.
We have a Restocking Fee which applies for return items with damaged package. Restocking Fee is 25%-50% of initial purchase.
• Do not tape the original packaging box — Restocking Fee will apply;
• Do not stick any shipping label/sticker on the original packaging box — Restocking Fee will apply;
• We recommend using stretch film to wrap the original packaging box. Use an additional shipping box or envelope to return the item.
You will be responsible for paying your own shipping costs for returning your item. Shipping costs are nonrefundable.

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All orders processed within 1 business day (excluding Sunday and holidays).

This fuel filter removes water, sediment, and particulate contamination from diesel fuel before it reaches the high-pressure injection system. Modern common-rail injection systems operate at extreme pressures — contaminated fuel causes injector wear, pump failure, and hard starting. Genuine Mack part — direct OEM replacement from the manufacturer.

Q: Which trucks does this fuel filter fit?
A: Fits Mack MP8 engines, Mack trucks. Verify your specific model and year before ordering. Contact us with your VIN for fitment confirmation.

Q: When should the fuel filter be replaced?
A: Replace at manufacturer-recommended service intervals or at first sign of failure symptoms. Refer to your truck maintenance schedule.

Q: Is this OEM or aftermarket quality?
A: Genuine Mack part — direct OEM replacement from the manufacturer.

Q: Can a clogged fuel filter damage the injectors?
A: Yes. Failure of this component can cause damage to connected systems and engine components. Replace at first sign of issues.

Q: What is included?
A: Complete MACK assembly, ready for installation. All necessary hardware and seals included where applicable.