What is the difference between Ford 9 inch diffs?

Difference Between Ford 9 Inch Differentials
The Ford 9-inch differentials have several variations and features that distinguish them from each other. Here are the key differences based on the search results:
1. Design and Performance:
– The 9-inch differentials feature larger diameter ring gears, creating additional distance between the centerline of the ring gear and the centerline of the pinion gear, known as hypoid distance, which impacts performance.
– The 9-inch is a dropout-style differential, with the gear set accessed through the center cover on the pinion side of the axle, not from the back like a more common carrier-type rear end.
– Ford produced different widths of 9-inch differentials, ranging from 57″ to 69″ measured from the outer flanges on each axle tube.
2. Identification and Strength:
– The Ford 9-inch differentials have a third member bolted to the front of the axle housing, and there is no traditional rear housing cover as found in many other rear ends.
– The strongest production Ford 9 case is made from nodular iron, identified by the letter N cast into the inside wall or front of most of the production third members between two of the strength ribs.
3. Modifications and Conversions:
– Precision in the placement and welding of the unit is crucial for the differential’s positive location.
– Most 9-inch Ford diff conversions may require a tail shaft modification to fit, and sometimes, sway bars may need to be altered.
4. Aftermarket and Racing Applications:
– Aftermarket nodular iron third members are available, and there are a wealth of replacement and upgrade parts for racing applications.
– The aftermarket produces complete Ford 9-inch third member assemblies with limited slip differentials and 28 or 31 spline axle shaft configurations, suitable for light-to-medium weight street vehicles.
5. Accessibility and Strength Improvements:
– The center section of the 9-inch rear end is removable, allowing for easier gear or differential swaps on a bench.
– Strange Engineering has designed improvements to the Ford 9-inch rear ends for the drag racing industry, increasing their strength in various ways.
These differences in design, strength, modifications, and aftermarket availability contribute to the versatility and popularity of the Ford 9-inch differentials in various automotive applications.
If you need more detailed information on any specific aspect, feel free to ask!

Why are Ford 9-inch rear ends so popular?

Its overall strength and availability are its greatest attributes, and 9-inch units are available with either 28- or 31-spline large diameter axles. The 9-inch rear end housings, also noted for their sturdiness, were built with case thicknesses ranging from . 150″ to .

What’s so great about a Ford 9-inch rear end?

The iconic Ford 9-inch has been the go-to diff for hot-rodders since day one. The brilliance of the unit is its ability to hold power, its quickness in changing gears, its vast range of available gear ratios, and the ease in which it can be setup. Shop our Ford 9-inch differential products here.

How much horsepower can a Ford 9-inch rear end handle?

GearFX offers a wide range of Ford 9-Inch rear ends, with strength ratings that range from 650-hp to 1000-hp and beyond. Their most popular setups are their S- and N-Series rear ends.

What is so special about a Ford 9-inch rear end?

One of the features which distinguishes this axle from other high-performance or heavy-duty domestic solid axles is that unlike other axle designs, access to the differential gears is not through the rear center cover; rather, in the Ford 9 inch, the rear cover is welded to the axle housing, and access to internals is …

How do I know what Ford differential I have?

Whether. It needs an additive or not usually that’s on those tags also. As far as identifying Ford. Gives most of the Fords will have the same format. So your super duties your f-150 is your Mustangs.

What is the different sline counts on a Ford 9-inch?

Ford 9-inch third members come with three common carrier bearing sizes, which include 2.892-inch (28-spline), 3.062-inch (31- and 33-spline), and 3.250-inch (35- and 40-spline). Larger race versions up to 3.812-inch are available for Trophy Truck applications with 40-spline axleshafts.

How do you identify a Ford 9 differential?

To recognize a locking or limited slip 9″ differential, look for a metal tag on one of the bolts that holds the center section to the housing. There is a gear ratio stamped on the tag. For example: The tag will say: 350 for 3.50:1 ring and pinion gear ratio.

How do I identify my Ford 9 inch gears?

Take a string and tape it to the passenger’s side of your driveshaft. Roll your car forward exactly 1 turn of the wheel. Crawl back under and see how many times the string has wrapped itself around the driveshaft and compare with available 9″ ratios.

What is the difference between Ford 9-inch rear ends?

Ford 9-inch rearends have a third “extra” pinion support bearing located at the rear of the drive pinion. Other rearends have only the traditional center two support bearings.

Who makes the best Ford 9-inch rear end?

Strange Engineering is the most recognized name in the aftermarket industry when it comes to Ford 9 inch rears. From high performance street cars to top fuel, Strange Ford 9 inch housings are relied on by more racers than all other manufacturers combined.