DDP40 | DD404 Front Differential | Dana Spicer | Full Locker | *DPX REMAN

DDP40 | DD404 | Dana Spicer Forward Differential with Full Driver Controlled Locker (DCL) — Remanufactured by DPX (40K GAWR)

The Dana Spicer DDP40 / DD404 (also known as DD-404 or DDP40-FWD) is a heavy-duty forward tandem differential with integrated power divider **and factory Driver Controlled Locker (DCL)** — commonly referred to by drivers as a "**Full Locker**". Remanufactured in Mansfield, Ohio by Discount Parts Exchange - DPX. Every unit is torn down, cleaned, inspected, and rebuilt to your exact ratio with new bearings, seals, and critical wear components. The DCL system allows the driver to engage a full lock for maximum traction in slippery, off-road, or severe service conditions.

Pairs with the RS404 rear-rear differential to form a complete tandem set.

Call DPX to confirm: 419-522-3320.

Highlights

• Model: DDP40 / DD404 Forward with Driver Controlled Locker (DCL / Full Locker)
• Axle Family: Dana D344 / D404 / D405 / D454
• GAWR: 40,000 lb
• Design: Single-reduction hypoid gearing with integrated power divider + Driver Controlled Air Locker
• Locker Type: Driver Controlled Locker (DCL) — full lock when activated by dash switch
• Axle Shaft Splines: 41
• Applications: Line-haul, dump truck, mixer, logging, heavy-haul, construction, and severe service where maximum traction is needed
• Dry Weight: ≈475 lb
• Warranty: 12-month, unlimited mileage (parts-only)

Available Gear Ratios & Part Numbers (DDP40 / DD404 Forward)

Original kit numbers shown in parentheses where applicable.

What’s Included

• Remanufactured DDP40 / DD404 forward differential with power divider and Driver Controlled Full Locker rebuilt to your requested ratio by Discount Parts Exchange - DPX
• 12-month, unlimited-mileage parts-only warranty
• DPX tech support during installation and initial run-in

Core Exchange Policy

• Required: Like-for-like, complete, rebuildable core
• Deductions may apply for: Cracked housings; burnt/missing internals; low-lube or water damage; non-matching cores
• Preparation: Core must be drained and palletized for pickup

Shipping Policy

• Ships via LTL motor freight to verified commercial addresses only
• No residential delivery — forklift or dock required at delivery

Image Disclaimer

Photos shown are representative; final appearance may vary by ratio and casting revision.

Call to Order

Call Discount Parts Exchange - DPX for pricing and ratio availability: 419-522-3320

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Reference Documentation

For detailed exploded-view diagrams, part numbers, and service data, download the official Spicer® Drive Axles AXIP-0200-32020 Illustrated Parts List covering the DS/RS404 / D404 / D405 / D454 axle family.
📄 Download Spicer DS404 / D404 Illustrated Parts List (PDF)

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