Return / Warranty Policies

A Returns Merchandise Authorization Form (RMA) must be completed prior to returning any parts.  You can find the form here: RMA Form.  Credit for returned parts will be issued at the time Sinister Diesel receives, inspects and approves returned merchandise, not when the RMA is submitted.  All products must be returned to Sinister Diesel and inspected before a credit memo is issued to the account. No returns will be allowed on drop-ships, add to stocks, special orders, discontinued items, or painted products.

Pay particularly close attention to order details at the time you receive your products to ensure that, should a return be necessary, all required parts and paperwork are included in the return shipment. 
Follow instructions and warnings on packaging before opening.  Pay attention to the label on the outside of the box to ensure your new parts match the vehicle to which you are fitting them. You are responsible for repackaging returned items to the same standard in which they were received. Poorly repackaged products are highly likely to be damaged during the return and thus credit denied. Customers are reminded to unpack, dry fit and examine all parts before installation.

Sinister Diesel Return Terms: 

  • For Non-Defective Parts: The item must have been purchased from Sinister Diesel within the past 30 days.  The original invoice number must also be provided. Products must be in the condition you received them in and must be in the original box and/or packaging.
  • For Defective Parts: The item must not have exceeded the manufacturer warranty period.
  • For All Parts: Sinister Diesel must first be contacted either by phone, or by completing the Sinister RMA Form. The form must be accurately completed, submitted and approved by the Sinister Diesel Returns Department prior to shipping your parts.   For warranty items, full explanation of the problem must be completely and accurately described.  The returned items must match the parts and descriptions given in the RMA.
  • Sinister Diesel reserves the right to refuse credit according to, but not limited to, the following conditions
    - Electronic devices are non-returnable.
    - The Item is returned for a non-warrantable reason.
    - The Item is not as described on the RMA.
    - The Manufacturer requires that you deal directly with them regarding defective items.
    - The Manufacturer's Warranty policy takes precedent on issuing of credits. Credit may then be issued upon the Manufacturer’s approval and will include applicable return shipping charges. No credit will be issued for labor expenses incurred. Other Manufacturer related fees may apply.
    - Items returned because of missing parts will be handled by the Manufacturer.  At Sinister Diesel's discretion, Sinister Diesel may act as a liaison to resolve the issue.
  • Restocking fees will be applied for all returned items. Typical 20% minimum, will be assessed upon receiving parts, any damage will cause restocking fees to increase.
  • Returns on international orders subject to applicable governmental, shipping and restocking fees as determined by Sinister Diesel

Warranty Terms and Conditions

  • Racing - The warranty for parts designated "race" covers manufacturer defects. Should a race part fail due to a defect in manufacturing as determined by Sinister Diesel, customer is entitled to replacement of that specific part.
  • Street - The warranty for parts designated "street legal" covers manufacturer defects. Should a street legal part fail due to a defect in manufacturing as determined by Sinister Diesel, customer is entitled to a refund, credit, or replacement of a comparable part.
  • All warranty determinations including but not limited to the cause of part failure and customer remedy will be determined solely by Sinister Diesel.
  • In all cases, the item must not have exceed the manufacturer warranty period.