BUILT TO HOLD MORE TORQUE AND KEEP TOWING TEMPERATURES DOWN

GM 6.6L DURAMAX 04.5-06 ALLISON TRANSMISSIONS

Find the BD RoadMaster Allison transmission package for your 2004.5-2019 Chevy Silverado or GMC Sierra 2500HD/3500HD with the 6.6L Duramax. Whether you're replacing a tired factory transmission or towing with a mildly tuned truck, the RoadMaster is built for reliability and peace of mind.

  • Built For Towing

    Increased clutch holding capacity for less slip under load.

  • Complete Package

    Includes a billet ProForce torque converter and deep aluminum pan.

  • 2004.5-2019 6.6L Duramax

    Direct-fit for Chevy Silverado & GMC Sierra 2500HD/3500HD trucks.

  • Dyno Tested

    Every RoadMaster Allison is dyno tested before it ships.

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FIND THE RIGHT TRANSMISSION PARTS FOR YOUR TRUCK

This table outlines applications for our RoadMaster Allison 1000 transmission and converter packages. We offer a direct-fit package for every 6.6L Duramax, from the 2001 LB7 through the 2019 L5P.

ApplicationEngineCommon YearsTypical ProductBest For
Silverado / Sierra 2500HD / 3500HD6.6L Duramax LB72001-2004RoadMaster Transmission & Converter Package (1064854SS)Replacing a worn 5-speed Allison in stock or mildly tuned LB7 trucks.
Silverado / Sierra 2500HD / 3500HD (4WD)6.6L Duramax LLY2004.5-2006RoadMaster Transmission & Converter Package (1064774SS)Replacing a worn 5-speed Allison in stock or mildly tuned LLY trucks.
Silverado / Sierra 2500HD / 3500HD6.6L Duramax LBZ2006-2007RoadMaster Transmission & Converter Package (1064864SS)Replacing a worn 6-speed Allison in stock or mildly tuned LBZ trucks.
Silverado / Sierra 2500HD / 3500HD6.6L Duramax LMM2007.5-2010RoadMaster Transmission & Converter Package (1064874SS)Replacing a worn 6-speed Allison in stock or mildly tuned LMM trucks.
Silverado / Sierra 2500HD / 3500HD6.6L Duramax LML2011-2016RoadMaster Transmission & Converter Package (1064884SS)Replacing a worn 6-speed Allison in stock or mildly tuned LML trucks.
Silverado / Sierra 2500HD / 3500HD6.6L Duramax L5P2017-2019RoadMaster Transmission & Converter Package (1064794SS)Replacing a worn 6-speed Allison in stock or mildly tuned L5P trucks.

WHY ALLISON TRANSMISSIONS FAIL AND HOW BD SOLVES IT

The Allison behind your Duramax is a proven transmission, but age, heavy towing and added power can push the factory clutch packs past their limits. BD Diesel's RoadMaster Allison is built for reliability and peace of mind. A modified valve body increases the torque holding capacity of the clutch packs, doubling the capacity of the C2 and C4 clutches, including the failure-prone C2. A BD Diesel deep aluminum pan adds 3.5 quarts of fluid to help keep temperatures down while towing, and every package includes a billet ProForce torque converter and is dyno tested before shipping.

  • High Mileage Wear

    Years of service wear out clutches, seals and internal components.

    The BD Difference

    A fresh RoadMaster is assembled with stock clutch counts and dyno tested before shipping.

  • C2 Clutch Failure

    The C2 clutch is a known weak point in the factory Allison.

    The BD Difference

    Our modified valve body doubles the torque capacity of the C2 and C4 clutches.

  • High Transmission Temperatures

    Heavy towing builds heat that breaks down fluid and wears internal parts.

    The BD Difference

    Our deep aluminum pan adds 3.5 quarts of fluid to help keep temperatures down.

  • Torque Converter Clutch Slip

    A worn converter clutch can slip, creating heat and lost power.

    The BD Difference

    The included billet ProForce converter provides reliable converter clutch apply.

What is included with the RoadMaster Allison transmission package?

The package includes the RoadMaster Allison transmission with a modified valve body, a BD Diesel deep aluminum pan with drain plug, and a billet ProForce torque converter. Every package is dyno tested before it ships.

Which trucks does the RoadMaster Allison fit?

It fits 2004.5-2019 Chevy Silverado and GMC Sierra 2500HD/3500HD trucks with the 6.6L Duramax diesel.

Will this transmission work with my tuned truck?

The RoadMaster is designed for stock or mildly modified Duramax trucks. If your truck is making significantly more power, contact our team to find the right transmission for your build.

How does the RoadMaster hold more torque than stock?

It keeps stock clutch counts, but the modified valve body increases the torque holding capacity of the clutch packs, doubling the capacity of the C2 and C4 clutches for less slip while towing.

How much extra fluid does the deep pan hold?

The BD Diesel deep aluminum pan adds 3.5 quarts of fluid capacity to help keep transmission temperatures lower, and its drain plug makes fluid service easier.

How long does installation take?

Installation takes approximately 9 hours.

What is the warranty?

The RoadMaster Allison transmission is covered by a 24-month parts warranty and a 12-month labor warranty.

What else should I buy with my transmission?

We recommend the 1041260 Billet Flexplate (available at a discount when bundled), the 1031361 Tap Shifter, the 1064041 Filter Service Kit and an Xtrude transmission cooler (1030606).