ALLISON 1000 L5P 6 speed Signature Series performance automatic transmission. These units are built to the most stringent tolerances by one expert technician from beginning to end, and each unit is signed by the technician when finished. This unit is rated at up to 1500HP (shafts will need to be upgraded) and has undergone over a year of rigorous R&D and performance testing. We don’t just say we have pride in our transmission, we literally put our name on it. This transmission features the following:
This transmission contains internal parts with the ability to hold up to 1500HP. However, this will require upgrading the shafts in the transmission. Unlike our competition, we do not leave optional upgraded parts out when we build our units. We do not have stages or levels as our transmissions ALL come fully built with no available upgrades other than billet shafts. We recommend upgrading the input shaft for any customer towing making over 850HP. As for the output, we recommend this for customers who will be doing boosted launches and making over 1000HP. We only recommend upgrading the intermediate shaft for those customers who will be producing over 1500HP and will be racing the majority of the time.
Not only do we have the best internal parts in our units, we have spent over $150k in valve body testing equipment to provide our customers with the best tested and performing valve body that money can buy. Each valve body is custom configured to our customer’s truck and individual tested prior to being installed in the transmission.
Please note that actual products may differ from images shown on our website. While we strive for accuracy in product listings, manufacturers may make changes to design, contents, color, or packaging without notice. Product images are for illustrative purposes only and may not represent the exact item you receive.
By purchasing, you acknowledge and accept that variations may occur and release OCDiesel from any liability related to product appearance differences.
Order Processing Time:
Orders are typically processed within 24-48 hours after the order has been placed.
Custom or special order items may take longer to process, typically 3-5 business days depending on the product and customization required.
Shipping Methods:
Standard Shipping (3-7 business days - location dependent)
Express Shipping (1-2 business days- location dependent)
Packaging:
All parts are securely packaged to better prevent any damage during transit. Fragile or high-value parts will be packaged with additional protective materials, such as bubble wrap or foam padding.
Shipping Rates:
Shipping rates vary based on the size, weight, and destination of the package. You can view the estimated shipping costs for your order during the checkout process before placing your order.
Order Tracking:
Once your order has been shipped, you will receive an email with the tracking number and carrier information. You can also track your order status by logging into your OCDiesel account.
USA Shipping:
We ship to the USA! (Except California) Please note that USA shipping rates and delivery times may vary based on destination. Customers are responsible for any customs fees, import taxes, or additional charges that may apply.
Not all products are stocked in-house. To ensure you receive your desired items promptly, please check for availability before placing your order. Some products may be backordered due to high demand or supply chain constraints, which could result in longer delivery times.
We strive to keep our inventory updated regularly, but availability can change quickly. For the most accurate information, contact the OCDiesel customer service team using either this link, or the chat bubble on the bottom right of this page.
Most items are eligible for return within 30 days of shipping, provided they are unused, in original manufacturer packaging, and in resalable condition. All returns & cancellations are subject to restocking and cancellation fees.
Returns must include a Return Authorization Number (RA #) and be shipped with tracking. Return shipping costs are the responsibility of the customer.
Custom/special orders, electronics, and digital goods are final sale—no returns, refunds, or exchanges.
For full return instructions, fee details, and conditions, click here.
