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IF BUNDLED WITH FLUID and EXTEND! Covers One Way Only
Power your truck with the SportlMonster Allison 1000 transmission - a legendary 5- or 6-speed automatic designed for heavy-duty performance and reliability. Known for its exceptional durability and smooth operation, the Allison 1000 is the ultimate choice for towing, hauling, and high-torque diesel applications. Engineered to handle extreme demands, it features advanced electronic controls, seamless shifts, and reinforced internal components to deliver long-lasting, consistent performance. Whether you're towing massive loads or doing daily driving, the SportlMonster Allison 1000 transmission provides the strength, precision, and dependability to dominate any road or job. It's built tough and engineered to last!
Note
In-stock transmissions usually ship the next business day.
Custom builds or out-of-stock units typically ship within 2–4 weeks.
Need it sooner? Call us — we can often make special arrangements.
We offer the most comprehensive coverage in the industry:
Extend warranties are optional add-ons available during checkout.
No — we offer a $299 Flat-Rate One-Way Shipping to any address, commercial or residential.
If you find a better rate, you're welcome to arrange your own shipping.
No — fluid must be purchased separately. We offer special discounted prices and even cheaper shipping options when you bundle with our fluid at checkout.
Returning your core is simple. Once you are ready to return your core, you can initiate the return process in one of two ways:
Please Note:
Our goal is to make this process as seamless as possible — if you have questions about your core return, just give us a call.