ATS Diesel Performance 313-906-4368 Stage 6 Allison Rebuild Kit GM 6.6L LML Duramax 6-Speed

How Core Charges Work

This part carries a $480.00 refundable core charge, added to your order at checkout. Return your old part and we refund it to your original payment method.

What is a core?

A core is your original used part — the one this new or remanufactured unit replaces. The core charge keeps rebuildable parts in circulation and keeps prices down for everyone.

Core charge refund timeline

Based on when we receive your core:

• 0 – 21 days100% refund
• 22 – 60 days80% refund
• 61 – 90 days50% refund
• Over 90 daysNot guaranteed — at DFIS's discretion

All cores are inspected on arrival. Incomplete, damaged or non-rebuildable cores may be denied credit or receive partial credit at our discretion. Refunds are processed within 3–7 business days after inspection.

How to return your core

1. Download the Core Return Slip and fill in your order and part information.
2. Drain all fluids (oil, fuel, coolant) from the core.
3. Reinstall any plugs or caps that came with the new part.
4. Wrap the core in a plastic bag so it can't leak, then pack it — in the new part's original box if you still have it — and secure it so it can't shift.
5. Put the completed slip inside the box.
6. Ship via UPS, FedEx, USPS or freight for large items. Insurance is recommended on high-value cores.
7. Email your tracking number to returns@dfispdx.com.

Important: a core refund can't be guaranteed without the completed slip inside the package and a tracking number.

Cores we can't accept

• Severely rusted or damaged beyond reuse
• Missing critical components
• Not drained of fluids
• Improperly packaged or leaking

Core department: returns@dfispdx.com  ·  503-235-1947