TRANSMISSION STAGE 4

The stock transmission is designed to handle the output of the stock engine, but not much more. Increase the durability of your drivetrain with a BD transmission. All transmissions come with BD's heavy duty transmission pan and most packages come bundled with our auxiliary transmission filter kit for added protection!

Additional Information

Transmission Kit; Incl. HD Transmission Pan And Fluid Filter Kit; Stage 4;

Part Type

Automatic Transmission Assembly

Product Overview

The introduction of the Allison 1000 transmission to the diesel truck market restored confidence in consumers that an automatic transmission can indeed handle the demands of exhaust braking without any electronic addition.

But while the Allison is suitable for stock applications, we've found that it does have its limitationsâ€" particularly when flywheel horsepower exceeds 370 horsepower. That's when the stock clutch packs can begin to slip, putting the computer in the dreaded “limp home” mode and once a clutch has slipped, the next time it will slip easier and easier.

At BD, we make several modifications to the Allison to meet the demands of high-performance and heavy-duty usage. A new convertor lock up valve, updated lube & regulator and pressure release spring has been installed.

With either the C1 or C2 clutches being engaged in all gears, this creates a weak link in the transmission. We designed 20% more friction surface and use high energy clutch material. We have also added extra frictions in the remaining clutches to improve holding capacity.

We have modified power pistons hydraulics and return springs are changed while main line oil pressure is raised to increase clamping force on the clutch packs.

If you've modified, or plan to modify your Duramax, the first step should be a BD Allison transmission. Call us today!

We also offer Build-it transmission rebuild kits with our modified parts for those that want to build their own performance transmissions.

New for 2010 we now have available exchange units for behind the Duramax LMM engine.

WARRANTY : 36-month / 150,000 mile limited warranty on non competitive, racing or sled-pulling applications. See warranty statement for further details.

These additional application notes are supplied by the manufacturer and collated from multiple year ranges. Not all of these notes may apply to every year or every variant. Please contact a StreetFX agent for clarification if required.

• 1990-2003 include auxiliary frame mounted full flow filter kit
• 30%-40% more clutch material with additional steels
• Accumulator body enhanced oil flow
• Added lube and support to output and intermediate shafts
• Added lube circuits to OD planet
• BD rigid aluminum heavy duty transmission pan
• Clutch Count: COAST CLUTCH 2
• Clutch Count: DIRECT 5
• Clutch Count: FORWARD 5
• Clutch Count: INTERMEDIATE 4
• Clutch Count: LOW REVERSE 7
• Clutch Count: OVERDRIVE 4
• Created lube circuit for towing in overdrive
• Creates positive clutch application
• Drilled and tapped direct and intermediate feeds to prevent leaks at case
• Each transmission is dyno tested
• Extra clutches and stronger internals
• Full shift kit with line mod valve to increase pressures
• Fully rollerized geartrain
• Handles up to 300% more power and torque than the stock transmission
• Has Stronger Internals
• Improved bearing designs
• Improved internal lubrication by adding high power boost valves
• Increase the durability of your drivetrain
• Increased cooler pressure
• Increased pressure to converter
• Machined center support
• Machined intermediate piston
• Machined low/reverse pressure plate
• Machined rear ring gear hub
• No Race Abuse Covered
• Not warranted for Race or Sled Pull use
• Pan adds 6qt extra oil capacity
• Pan heat-dissipating fins keep temperature down
• Pan magnetic drain plug
• Pan reduces case flex
• Pan reduces internal oil leakage
• Re-programmed accumulator body
• Replaced all aluminum planetaries with steel
• Revised oil circuits
• Revised Oil Circuits/Extra Clutches
• Reworked front pump
• Solenoids hard wiring providing high temperature resistance
• Sure-loc snap rings
• Tighter clutch packs that provide a quicker shift
• Upgrade supports
• Upgraded sprags

Images are supplied by the manufacturer and may be generic. While all efforts are made to provide accurate pictures, there may be differences in the actual product, such as colour, quantity, version, or included components. Please carefully review the description and specifications for details on inclusions or any variations. Some items may be sold individually or in sets, and images may occasionally depict additional products or quantities not included in your purchase. For assistance or clarification, please contact customer support.

Product Details

Product Downloads

#	Document Type	Download
1.	Installation Instructions
2.	Catalog

Installation guides, warranty details, and other supporting documents are provided by the supplier. In some cases, these files may originate from regions outside your locale, meaning instructions, warranty procedures, and images may not fully align with your specific vehicle or region (e.g., LHD vs. RHD differences, return policies, etc.). If you need clarification, please contact a StreetFX support agent.

Reference Information