Your satisfaction with Modern DriveLine products is always our goal.

We understand it is sometimes necessary to exchange or return an item therefore we wish to make this process simple.


  To get started simply call our offices at  –  208-453-9800 
between the hours of 8:00 am to 4:30 pm Monday to Friday  MST.
   to be issued a Returned Merchandise Authorization #

No item(s) will be accepted for return without an RMA #


Returns and Replacements not purchased directly from MDL MUST go thru the original place of purchase.

For items purchased directly from MDL, you may return items within & up to 90 days of receipt.
 – After 90 days, items no longer qualify for return.-
** Items that have not been returned within 45 days after the issue of RMA #  no longer qualify for return. **

All returns must be freight pre-paid.  Items returned through COD cannot be accepted by MDL.


Items that meet the conditions for return are:

  • New item(s) in original packaging and original/unaltered condition. 
     – Unaltered is defined as: unrefurbished, the item cannot be painted or have the finish removed, or any item(s) requiring major cleaning upon arrival at MDL, any item(s) having rusted or oxidation, the items may not exhibit physical, structural, or cosmetic damage or change to the item(s) of any kind.
        –  The item(s) Must be in re-sellable condition.
  • A used core, as long as it is shipped in the box that contained the product when new.
  • Any item(s) received by you the customer in a damaged or defective condition.
  • Any item(s) received by you the customer in error from MDL

 ** Items that have not been returned within 45 days after the issue of RMA #  no longer qualify.    


Returns are subject to a minimum 15% Restocking Fee for the following conditions.

  • The buyer changes their mind about a purchase
  • No longer needed / wanted
  • item(s) misidentified by the customer during the ‘quote/purchase process’.
  • Item(s) Bought by mistake
  • Better price available elsewhere
  • Altered products: Which are defined as: refurbished, painted, or any removal of finish of the item(s), any item(s) requiring major cleaning upon arrival at MDL, rusted or oxidized item(s), exhibiting physical, structural or cosmetic damage, or change to the item(s) of any kind.

This fee may also be charged based on the determination upon inspection of the returned parts.  



When returning an item please include a copy of the invoice/credit memo and any relevant information concerning the reason for returning the item and if you desire a refund or exchange.
The RMA Number must be noted on correspondence and on the outside of the package.
Secure your merchandise in the original packing material. if available.
Take the package to your preferred shipping carrier. The buyer is responsible for all shipping costs (both ways).
If a return address label has been provided, place it over the original shipping label on your package.
Don’t forget to insure the shipment for the value of the item.  


  EXCHANGES: If you are exchanging parts (restocking fee waived) Indicate your preference on the receipt. 
–  We will issue an in-house credit if you are not ready to purchase.
Modern DriveLine reserves the right to have 30 business days to review any and all returns, but we typically handle returns within a few business days.
Due to the nature of our products, reviewing returns can be a long and involved process.
Stick with us… We appreciate your patience and understanding.  



Modern Driveline Inc. guarantees all products to be free from defects in materials and workmanship for normal use and service.
–   Manufacturer authorization may be required before a warranty claim can be completed.
MDL shall not be liable for any special, direct, indirect, incidental, or consequential damages, that might be claimed as a result of the failure of any part, incorrect installation of item(s), including claims for delay, loss of profits, or labor.
MDL shall not be liable for any damage or injury to persons or property resulting from improper installation, misuse, abuse, normal wear, or any damages due to accidents, collisions, and improper handling or installation of any part subject to this warranty.
MDL assumes no responsibility for labor, installation, removal, diagnosis, loss of vehicle use, lost time, inconvenience, pain, and suffering, or any other consequential expense or damages incurred by the purchaser.
MDL’s obligation under warranty shall be limited to repair or replacement, after review, of any item(s) to be proven defective.  

MDL will refund shipping charges under these conditions.

  • if the wrong item was sent to the customer or if the item(s) is defective or damaged upon arrival.


Contact one of our trained problem solvers if you have any questions or concerns:  208-453-9800  We’re here to help.



Order Changes and Cancellations

Any order can be changed or canceled up to the time of shipment

If the order has already shipped the order may still be canceled but there will be cost incurred.
Please contact us as soon as possible if you wish to make any changes and we will do our best to accommodate your request.

The customer is responsible for any unrecoverable costs.

  • shipping, resulting from cancellation of an order after shipment.
  • A restocking fee may be applied.

Shipping Policy

Costs of shipment, handling, and insurance will be added to the final invoice.

All shipments from MDL are via UPS ground unless requested otherwise.

MDL ships via UPS or United States Postal Service only
Should the customer want to use a different carrier they may make arrangements for pick up from MDL

the MDL shopping cart estimates the shipping charges.
MDL reserves the right to change the charged amount when the actual shipping charges differ more than 10% from the estimate.

Estimated shipping charges are US domestic only.

MDL does not ship COD.

MDL requires the shipping address to match the billing address of the credit card used.

It is MDL’s policy that the customer’s credit card is not charged until the time of shipment.

Note: Items that have not been returned within 45 days after the issue of RMA #  no longer qualify.


Once your return is received and inspected, we will send you an email to notify you that we have received your returned item.
We will also notify you of the approval or rejection of your refund.

If you are approved, then your refund will be processed, and a credit will automatically be applied to your credit card takes up to 3 business days, credit through Square 5-7 business days or Pay Pal 5-business days.

Late or missing refunds

If you haven’t received a refund yet, first check your bank account again.

Then contact your credit card company, it may take some time before your refund is officially posted.

Next, contact your bank. There is often some processing time before a refund is posted.

If you’ve done all of this and you still have not received your refund yet, please contact us at {email address}.




We only replace items if they are defective or damaged. If you need to exchange it for the same item, contact us at: 208-453-9800  to begin this process.


Shipping returns

To return your product, you must contact us by phone at  208-453-9800

You will be responsible for paying for your own shipping costs for returning your item. Shipping costs are non-refundable. If you receive a refund, the cost of return shipping will be deducted from your refund.


Depending on where you live, the time it may take for your exchanged product to reach you may vary.


Return Address:

Modern Driveline
4216 Capital St.
Caldwell, ID


Need help?

Contact us at sales@moderndriveline.com for questions related to refunds and returns.



Modern Driveline Inc. guarantees all products to be free from defects in materials and workmanship for normal use and service.

Should any item be determined to be out of the realm of normal use & or service it may be deemed not to qualify for Warranty or refund.

The warranty on all MDL items is 1-Year, the only exception to this is a complete package purchase.
In which case the warranty period is extended to 2-Years.

  • Definition of a complete package is: a new Tremec transmission T5, TKX, Magnum, Magnum F or Magnum XL accompanied in the same purchase by a minimum of $1500.00 of supporting hardware.
  • MDL modified transmissions added value above the price of the transmission is not applicable to the $1500.00 that makes up a complete package.

The warranty period on an MDL rebuild transmission is 1-Year.

Manufacturer authorization may be required before a warranty claim can be completed.