Cometic Dodge Cummins Diesel 3.9L 4BT 4.188 inch Bore .066 inch MLX-5 Headgasket C5591-066

In-stock orders are processed within 48 hours; transit time is additional.

International orders include export processing and customs clearance. Duties, taxes and brokerage are extra; final freight charges may change after remeasurement.

Request return authorization (RMA) within 30 days of delivery for eligible items. Keep items unused and uninstalled, with original packaging and accessories. Electronics, liquids, special orders and other categories are excluded.

Email sales@frsport.com with RETURN and your order number in the subject to request an RMA. Please wait for return authorization before sending your item back.

Wrong part/size or change of mind: a 20% return processing fee applies, plus applicable shipping costs.

Original shipping is non-refundable. For orders shipped free, the actual outbound shipping cost is deducted from the refund. Return shipping is prepaid by the customer.

After payment capture, cancellations and refunds generally incur a 5% processing fee, except for our error, confirmed defects or confirmed carrier loss. The 5% and 20% fees do not stack; only the greater applicable fee applies. Store credit waives the 5% fee, but applicable return fees remain.

Missing, incorrect or transit-damaged items: report within 3 business days of receipt with photos of the product and packaging.

For defective items, contact us for help with the manufacturer's warranty process. The manufacturer decides the claim.