We take pride in our work! Transmissions are assembled in a clean and controlled environment. Every piece is hot tanked, ultra sonic cleaned, and personally inspected for even the slightest flaws.  A series of highly specific measurements, function and piston apply tests are performed before the transmission leaves the stand. 

DHD is THE source for Performance Built Allison Transmissions! Our industry leading equipment, staff, and years of knowledge in the pulling and racing industry ensure that you are getting the best performance built Allison transmission on the market to date! 

• Clutch Pack Setup and Machining
• High Performance Frictions
• Precision Gaskets and Seals
• All New Factory Allison Torrington Bearings
• New Molded Clutch Apply Pistons
• Upgraded Sleeved C2 Hub w/ Machined P1 Sun Gear
• New Bushings Throughout
• Turbo-Tony Valve Body Rework
• Upgraded Line Pressure Controls
• DHD Billet Stator Torque Converter
• Genuine Allison Stamped Deep Transmission Pan
• Genuine Allison Spin-on and Deep Pan Filter
• New Pressure Switch & Wiring
• New Solenoids

You will be contacted about your shipping arrangements.

Core credit returns will be accepted within 180 days of original purchase. After 180 day core credit refunds will be at the discretion of SDS. Core returns after 120 days will be issued SDS store credit only.

To return your product core for credit, fill out the Return Form. SDS will email you with an RMA number and detailed return instructions. Please wait for shipment instructions before shipping any cores, many cores will be sent directly to the manufacturer.

SDS recommends using a carrier that provides package tracking to ensure your product gets back safely and quickly. You will not be reimbursed for shipping costs incurred in shipping the core. The credit card used for the purchase of the product giving rise to the core return will be credited with the core's original invoiced value after inspection.

Please drain all fluids, if any, from the core. The core returned must be a like-for-like make, model, type and part number. Cores will not be accepted from a salvage or junkyard. Cores that have been disassembled or have missing and/or damaged major components will not receive full core credit.