N400-RR | Dana N-400 Rear Rear Differential | Remanufactured – Exchange Required

Dana N-400 Rear Rear Differential — Rebuilt by DPX

The Dana N-400 rear rear (tandem) carrier is rebuilt for Class 8 International/Navistar trucks. Each carrier is disassembled, cleaned, inspected, and rebuilt to your exact ratio using OEM and premium aftermarket components. Units are verified for backlash, gear mesh, and seal integrity. Rebuilt in Mansfield, Ohio by DPX.

Call DPX to confirm: 419-522-3320.

Quick Specs

• Model: Dana N-400 (Rear Rear Tandem)
• Application: International / Navistar (Class 8)
• Axle Shaft Splines: 36, 39, or 41 (verify before ordering)
• Ratio Options: 3.06 to 7.81 (see table below)
• Weight: ~300 lb carrier assembly
• Condition: Rebuilt exchange (like-for-like core required)
• Common OE Codes: International 514-GDCR / Code 14GDC

Why Choose DPX

• Rebuilt to your exact ratio — backlash, mesh, and seals verified
• Heavy-duty durability — ideal for on-highway fleet applications
• Straightforward install — painted, tagged, and prepped for drop-in
• Real support — tech help from DPX during install & initial run-in

Gear Ratio Options & Part Numbers (Dana N-400 Rear Rear)

Confirm ratio and spline count prior to ordering.

Casting & Assembly IDs

• Seal Retainer Cast: 454718K1
• Cap & Carrier Casting: 401CF102
• Cap Casting: 401CP100
• Finished Carrier Assembly: Dana 401CS101-X

What’s Included

• Complete rebuilt N-400 rear rear carrier rebuilt to your requested ratio by DPX
• Painted & tagged for installation
• Tech support from DPX during install & initial run-in

Core Exchange Policy

• Like-for-like, complete, and rebuildable core required
• Deductions may apply for cracked housings, burnt/missing internals, low-lube or water damage, or mismatched units
• Call for pickup return instructions

Shipping

• Method: LTL motor freight to verified commercial addresses
• Requirements: Forklift or dock — residential delivery not available
• Liftgate: Available by request (additional charge may apply)

Lubricant Spec & Recommendation

• Recommended: Spicer FE 75W-90 synthetic gear lubricant (or equivalent meeting OEM specs)

Detroit Locker / No-Spin Options

Traction upgrades available for the N-400 rear rear. Verify spline size before ordering:

• 306S-99 — 1.850" (36-spline)
• 306S-98 — 2.00" (39-spline)
• 306S-100 — 2.100" (41-spline)

Order & Support

Call for pricing & availability: 419-522-3320
Have your ratio and spline count (36 / 39 / 41) ready to speed things up.

Curious What a Ratio Change Will Do for Your Truck?

Use our free Road Speed Calculator to plug in your tire size, current ratio, and target speed/RPM. See exactly what a 3.55, 3.73, or 4.10 would do before you buy.

Open Road Speed Calculator →

DPX — Ohio’s Premier Heavy-Duty Drivetrain Rebuilder | Built to Perform. Trusted to Last.