The quickest way to know is to look for a direct identifier on the axle or to compare key physical features: ring-gear markings, axle tube size, and the number of splines on the axle shafts. In general, Dana 44 is heavier, uses thicker tubes and a different spline count than Dana 35. If you can’t see clear markings, VIN/build sheet data can confirm the option from the factory.
This article lays out practical steps you can take to identify which axle your Jeep uses, whether you’re planning a repair, upgrade, or simply curious. We’ll start with direct markings, then move to measurements you can take with basic tools, and finally how to use factory documentation when available.
Direct axle markings you can read
First, scan the axle housing and differential cover for any stamps or labels. Direct identifiers are the most reliable when present, and they won’t require disassembly beyond exposing the cover or a small tag.
- Look for raised lettering or stamping on the differential cover or housing that reads DANA 35, DANA 44, or a model code you can cross-check with Dana’s catalog.
- Inspect for a small metal tag or engraving on the passenger-side axle tube or near the breather that lists the axle model or ratio.
- Note any casting numbers on the housing (often found near perches or control-arm brackets) and cross-reference them with Dana/Jeep axle catalogs or reputable online databases.
Direct markings are the most straightforward way to identify the axle, but if markings are missing or painted over, you’ll move to measurements and documentation to confirm.
When markings are unclear or missing
If you can’t see clear axle markings, proceed with measurements and documentation checks. A careful approach reduces the risk of misidentifying the axle, which is important for parts compatibility and safety during upgrades.
Physical measurements you can take
Measuring key features can differentiate Dana 35 from Dana 44, especially when direct markings aren’t available. Use caution and support the vehicle securely before probing with calipers or rulers.
- Axle tube diameter: Use a caliper to measure the outside diameter of the axle tube at a mid-point between the perches. Dana 35 tubes are typically around 1.75 inches in diameter, while Dana 44 tubes are thicker, often around 2.0 inches. This is a strong visual cue but can vary by model and year.
- Overall width and hub/shaft area: The Dana 44 tends to have a wider rear end and thicker, more robust housing and drivetrain components. Compare the distance from the wheel mounting surface to the opposite wheel mounting surface if you have two axles to compare, but for a single axle, rely more on tube diameter and spline checks.
- Axle shaft count (splines) at the end of the shafts: If you can access the end of the axle shaft (behind the drum or rotor), count the number of spline teeth. Dana 35 families commonly use 27-spline outer axles, while Dana 44 variants typically use 30-spline outer axles. Note that there are exceptions depending on sub-models and years; count carefully or consult reference resources if you’re unsure.
These measurements are useful, but they aren’t foolproof due to model-year variations and aftermarket parts. Use them in combination with markings or documentation for the most accurate identification.
Using VIN/build sheet and factory documentation
If markings and measurements aren’t conclusive, factory documentation can confirm the axle option. Your vehicle’s VIN and build sheet (or a dealer-drawn factory report) are the most definitive sources when accessible.
- Check the door jamb or inside the glove box for a factory sticker or window sticker that lists axle type or gear ratio. Some Jeeps include an “Axle” code or “Rear Axle” option that you can decode against manufacturer references.
- Request a factory build sheet or a VIN-based decode from the dealer or official service portals. These documents often specify the axle code (for example, a 44- or 35-series designation) and the gear ratio, which can help confirm the specific Dana model.
- Consult reputable online VIN decoding resources or community databases that map Jeep VINs to axle options. While not official, these sources can be very accurate for common configurations and years.
Documentation is the most reliable method when visible a direct stamping is absent or ambiguous. If you can’t access a build sheet, a local Jeep technician or dealership can often pull the official option list from the VIN.
Practical notes and caveats
Keep in mind that aftermarket parts, replacements, or reconditioned axles can alter markings or tube sizes. Some owners replace differential covers, tags, or entire housings, which can obscure the original Dana designation. If you’re planning work based on the axle choice (such as upgrading gears or installing a upgrade kit), verify with multiple methods to avoid mismatches.
Summary
To determine whether your Jeep has a Dana 35 or Dana 44, start with any direct markings on the differential cover or axle housing, then verify with physical measurements like axle tube diameter and spline count on the axle shafts. If markings and measurements aren’t conclusive, use the VIN/build sheet to confirm the factory axle option. Combining these methods provides a reliable answer and helps ensure correct parts and upgrades for your vehicle.