12Ms520M Genuine Mack Engine Control Module

At Truck To Trailer Parts, timely and reliable delivery is essential to your business. Most orders ship from our North Carolina warehouse, and in-stock parts ordered by 7:30 PM ET Monday–Friday typically ship the same business day.

Processing & Dispatch

Estimated shipping times below are transit times and don't include processing. In-stock parts ordered by 7:30 PM ET Mon–Fri usually leave the same business day; items that need extra prep ship within 24–48 hours. We dispatch Monday through Saturday, excluding major U.S. holidays. Need an exact estimate? Contact us — and note that address changes after dispatch may carry carrier fees, payable by the customer.

Shipping Methods & Transit Times

Free Shipping

We offer Free Shipping on eligible items within the contiguous 48 United States. Outside this region, we'll provide an accurate quote on request. Some oversized or freight items may not qualify unless specifically noted.

Freight & Oversize Shipments

Oversized shipments travel via Freight/LTL, designed for commercially zoned properties — deliveries to non-commercial addresses may carry additional charges. When receiving freight, inspect the package for damage and note exceptions on the delivery receipt before signing. Extra services like a lift gate incur carrier fees payable by the customer.

Canada & International

For Canadian shipments, customs duties, taxes and brokerage fees are the customer's responsibility — please pay promptly to avoid delays. We ship internationally too: if your location isn't supported at checkout, contact us for a custom quote. International customers are responsible for duties, taxes and customs charges.