What axle is in a Ford F550?

The Ford F-550 uses a heavy‑duty front axle built by Dana/Spicer and a robust rear axle designed for commercial payloads; the exact axle model and gear ratios depend on the year, configuration (SRW vs DRW), and whether the truck is 4x4 or 2WD.

As a member of Ford’s Super Duty family, the F-550 is engineered for demanding service from fleets, contractors, and utility operators. Axle choices have evolved across generations and options packages, but the core arrangement remains a heavy‑duty front axle paired with a large, rear axle capable of high GVWR ratings. Specifics—such as axle model numbers, gear ratios, and whether Meritor, Dana/Spicer, or Ford components are used—vary by production year and configuration.

Front axle configuration

Here is what you typically find on the F-550’s front axle across common configurations.

• Front axle: Dana/Spicer heavy‑duty solid axle, generally aligned with a Dana 60‑class design for most 4x4 F‑550 models.


• Variations exist by year and package; some older or alternate-market configurations may use a different Dana/Spicer unit or a Ford‑built equivalent in limited cases.

In practice, the front axle on most recent F‑550s is a sturdy Dana/Spicer solid axle configured for the rigors of 4x4 operation, with design choices evolving over time to support payload and off‑road capability.

Rear axle configuration

Rear axle setup for the F‑550 is similarly heavy‑duty and varies with whether the truck is SRW (single rear wheel) or DRW (dual rear wheel), as well as by year and option package.

• Rear axle: heavy‑duty units sourced from Dana/Spicer or Meritor, chosen to support high payload capacity; configurations include SRW and DRW with large ring‑gear designs.


• Gear ratios and exact housing models differ by model year and drivetrain option, with DRW versions often pairing with larger rear‑axle assemblies than SRW examples.

Because the F‑550 serves in work fleets, the rear axle is built to maximize payload and stability under load, with variations reflecting the truck’s intended use and region.

How to verify the exact axle on your F-550

To determine the precise axle model and gear ratio on a specific F‑550, use these steps:

1. Locate the vehicle identification number (VIN) and use Ford’s official vehicle data service or a trusted decoder to pull axle options tied to that VIN.


2. Check the original window sticker or the build sheet (often called a VIN build sheet) for axle type and gear ratio specifications.


3. Look for an axle tag or stamping on the differential housing itself, which typically lists the axle code and gear ratio.


4. Consult the owner's manual or service manual for axle specifications, or contact a Ford Commercial/Pro dealer with the VIN for exact details.


5. For fleet vehicles, ask the fleet manager or fleet maintenance portal where build data is archived.

Knowing the exact axle is vital for maintenance, parts compatibility, tire sizing, and any potential axle‑swap or upgrade work.

Summary

The Ford F-550’s axle setup centers on a heavy‑duty Dana/Spicer front axle paired with a robust rear axle (often Dana/Spicer or Meritor), with exact models, gear ratios, and configurations varying by year, drivetrain (SRW vs DRW), and 4x4/2WD setup. For precise specification, consult the vehicle’s VIN data, build sheet, or a Ford commercial dealer.

What size axle is a Ford F-550?

With 10.8" (275 MM) Axle Size. Drive Shaft - Front Axle Drive. LHD 4WD (Part Time Drive).

What is the gear ratio of the Ford F-550?

4.88 Ratio
Ford F-550 Super Duty 2017 and Up M300 4.88 Ratio Gear Package Revolution Gear and Axle.

What Fords have Dana 60 axles?

• 1974–1979 F-250 (optional)
• 1999–2011 F-250 (optional)
• 1979, 1986-2011 F-350 (optional)
• 2000–2004 F-450/F-550.
• 2011-2016 F-250/F-350.
• 2017-2024 F-250/F-350.

What's the difference between a F-450 and F-550?

The main difference is that the F-550 has a higher payload capacity, while the F-450 pickup truck excels in towing capacity. The choice depends on your needs: select the F-450 for maximum towing, especially with the pickup configuration, and the F-550 for applications requiring heavier payloads, like upfitting with a dump or service body, which is a common F-550 chassis-cab configuration. 
You can watch this video to learn about the differences in frames and springs between F450, F550, and F600: 53sJB ReviewsYouTube · Jun 12, 2024
Ford F-450

• Best for: Maximum towing. 
• Key features: Available as a conventional pickup or chassis cab. 
• Towing: The pickup truck configuration is ideal for high towing capacity, reaching up to 40,000 lbs when properly equipped. 
• Payload: The chassis cab version has a lower payload capacity than the F-550. 
• Suspension: The pickup truck uses a different rear suspension setup than the chassis cab, which is designed for a more rigid ride. 

Ford F-550

• Best for: Maximum payload capacity. 
• Key features: Only available as a chassis cab. 
• Towing: Has a slightly lower towing capacity than the F-450 pickup, with a maximum of 34,300 lbs. 
• Payload: Designed for heavy-duty upfitting with dump, service, or box truck bodies, which increases payload capacity. 
• Suspension: Features a more robust rear axle and suspension to handle heavy loads. 

This video compares F450 pickup to F450/F550 chassis cabs: 57sBig Truck Big RVYouTube · Aug 31, 2016
Which one should you choose?

• Choose the F-450 if: Your primary need is to tow large trailers and gooseneck trailers. The pickup configuration is the clear winner for maximizing towing capacity. 
• Choose the F-550 if: You need to carry heavy loads on the truck itself, such as a utility body, dump body, or large service body. The chassis cab is built for this purpose with a higher payload rating.