Cores are to be returned within 15 days or receiving the new unit, unless prior arrangements have been made. Please have the name that the differential was sold to and your order number written clearly on the box being shipped back to us to expedite the return being processed. Please complete Core Return Slip.
Core charge will only be refunded once your existing differential is postmarked to us within 15 days of delivery of the differential purchased from us, your existing differential is fully inspected, your existing differential is found to be of the same type as purchased and in rebuildable condition after inspection.
We're able to offer rebuilt and performance differentials at a reasonable cost due to the use of cores. A "core" is your original used differential that is returned to our diff builder to be recycled into a new, fully-rebuilt diff. If we did not have cores available, and had to buy new factory differentials from BMW, our performance diffs would be four times the price they are now. To keep this upgrade feasible for the entire enthusiast community we rely on having your good, reusable core returned to the diff builder (Diffsonline) within fourteen days of receipt of your new diff. In order to cover the cost of sourcing another used diff, a separate core charge, in addition to the advertised price, is applied to your order at the time of processing. This core charge can be refunded when you send back your original diff. Only complete and reusable cores will be eligible for a refund (no blown out, abused, or modified cores please). You must return a diff equal in components and accessories to the one sent to you. We do not accept unauthorized returns.
Please e-mail, or call us regarding any problems with an order for assistance or return authorization number. Returned parts must be unused, in original condition, and in original unopened packaging and received by Diffsonline no later than 30 days after sale for a refund. No return will be accepted without a return authorization number. No returns are allowed on custom built products, including but not limited to differentials, and any custom fabrication. Returned items are thoroughly inspected before a refund is issued. There is no refund on special order items. A 20% restocking fee will be charged to all returns not due to our error. There is no refund for any shipping charge on returned items.
Diffsonline reserves the final say on what is a good core, as the core HAS TO BE ABLE TO BE USED FOR THE NEXT CUSTOMER!