Tag Archives: Axles

Moser Custom Alloy Axles

Moser Custom Alloy Axles are the best in the business. We begin with premium quality alloy steel that is forged in Moser designed tooling, induction heat-treated to optimize torsional strength, and then 100% magnafluxed.

Differential Repair and Installation Instructions

You can expect many years and many miles of dependable use from your differential if it is set up properly and if you use only top quality parts. You already have quality parts if you bought them from West Coast Differentials. By following these instructions carefully, you will achieve proper set up. We have successfully set up thousands of differentials without using a pinion depth setting tool. We sincerely hope that these instructions are helpful.


Balljoint Writeup – 95 Bronco

This was a pretty complicated one for me, living in the rust belt and never done this before. Just make sure that you have a Haynes manual by your side! Remember, this was done on a 95 Bronco. Your setup may vary.


Axle swap – Chevy 1/2 ton to 3/4 ton

One of the nice things about building a full size 69-91 Blazer/Jimmy is the interchangeability of the front and rear axles, find out what it took to replace the weak 10-bolt axes on project “UAV”.


Axle Shaft Technology

A part of the BV-60 project, this article also stands alone as a pretty thorough discussion and examination of modern axle shaft technology – from the materials and heat treatment methods used to the forming of splines.


Dana 60 Bible

This monster is some 66 pages long, and contains just about everything there is to know about Dana 60 Front Axles. Sections include description, identification, dimensions, specifications, pictures, Bill of Materials listings, parts interchange, assembly specifications, yokes, gears, lockers, axle shafts, bearings and seals, lockout hubs, u-joints, as well as technical facts, how-to articles, and a HUGE FAQ. Updated frequently.


Axle related PDF files

** NEW ** 1 Ton Axle Manual (compiled from Military Manuals)
Superior CrMo front axles
ARB application chart
Auburn spools and mini-spools
Dana Drivetrain Catalogue Jan 03
Lockright apps ford truck
Moog’s front axle ball joint adjustment tech bulletin
Yukon Gear Ring and Pinion installation instructions
Warn Axles
Detroit Locker apps HeavyModelList
Detroit Locker brochure
powertrax no-slip d60 ford apps
West Coast Diff 14 bolt catalogue

Axle Identification Chart

Illustrations of most major axles.


14 Bolt Tech Tuesday

The questions below are answered here 14 Bolt FF Information

What do you know about this axle?

Is there anything stronger?

What does it cost?

Where can I find one?

How easy are parts to find?

What swaps are available?

Is it worth upgrading to from a 12 bolt?

Which gears are available?


Ford 9 Inch

I’ve noticed that there’s a lot of misinformation floating around out there about the Ford 9″ axle and what can be done with it. Some people are of the mindset that the 9″ is inherently weak because the outer diameter of the ring gear is .75″ smaller than the outer diameter of a Dana 60 ring gear. This is not the case. I won’t go into all of the different factory cases and applications, because there are already hundreds of websites and articles dedicated solely to that.

The Theory:

All modern differentials utilize “hypoid” gears. A hypoid gear set is essentially a cross between a spiral bevel gear and a worm gear. Hypoid gears are a type of spiral bevel gear whose axis does not intersect with the meshing gear. This means that as hypoid gears rotate, the teeth “slip” against each other.

Spiral bevel gear:

Worm gear:

Hypoid gear:

Now that the basics are out of the way, why is the 9″ remarkably strong when compared to some of the physically larger axles that are produced? Well, the amount that the teeth slide against each other can be directly correlated to the design of the gear set. The largest contributing factor is how far the pinion gear sits above or below the centerline of the ring gear. The farther the offset, the more the gears slip. This is referred to as a “high hypoid” design. Now, while designs like this tend to produce more heat and rob more power during operation, there is an extremely important silver lining. High hypoid gears generally have more contact area between the ring gear and pinion gear. This is because higher hypoid designs lean more toward the worm gear end of the spectrum. While it may not seem like a big deal in the grand scheme of things, it surely is. When comparing tooth overlap and cross sectional area of each tooth, a Dana 60 (depending on ratio and exact gear design) has only 50%-70% of the contact area that a 9″ does. In addition, the 9″ incorporates a third pinion support just like the revered 14 bolt full floater. Do I have your attention?

While the third bearing might seem insignificant in the grand scheme of things, it is EXTREMELY important. Deflection is what causes most major ring and pinion carnage. The third pinion bearing is placed on the opposite side of the pinion head when compared to the two traditional pinion bearings. Because of this “double shear” style of support at the pinion head, deflection is greatly reduced. Although it can never be completely eliminated, deflection control with a third bearing incorporated into the pinion is superior to any “standard” two bearing setup.

The Options:

Ford 9″ differentials can be used with a variety of axle sizes. Beware, as carrier bearing sizes are generally specific to the spline count of the carrier. 9″ carriers can be had in 28, 31, 33, 35, and 40 spline varieties. Because of size constraints, the only 40 spline carriers available are spools.

Third member housings are also available in a variety of configurations and materials. Nodular iron and aluminum dominate the scene. There are several different styles of pinion supports available as well, some stronger than others. Fairly new to the game is a company named True Hi 9. They are the only manufacturer of high pinion 9″ housings. Currie has a similar claim, but their differentials use Ford 8.8 gears. Also, True Hi9 differentials use a “load bolt” that presses against the back of the ring gear to further reduce deflection.

Because of the high hypoid design, and tremendous aftermarket following of the 9″, a wide variety of gear ratios are available, all the way from 2.86:1 to 7.33:1.

Since the Ford 9″ has been the axle of choice for desert racers and high power street rods for years, there are an incredible number of housing manufacturers. Some of the most popular in the rock-crawling world are Spidertrax, Diamond Axle, and Crossed Up Off-road.  However, if one chooses to venture outside the rock-crawling scene, the possibilities are endless, and there is almost no limit on the money that can be spent on a housing.

Front Axle:

Since anything smaller would essentially be a waste of the strength of a 9″, most people run a 9″ differential and use everything else from a Dana 60. Dana 60/70 35 spline shafts will fit directly into a 35 spline 9″ carrier with no modification. This means that the tremendous aftermarket support that the Dana 60 receives in terms of axle shafts, knuckles, etc., can be combined with the following of the 9″.

Rear Axle:


Although arguably weaker than a full floating setup, a semi-floating axle is cheaper to build and generally weighs less. Building a semi-floating 9″ rear can be done with most, if not all, of the spline counts available. Bearing cups and retainer plates are available from a number of sources, as are the correct bearings to support the axle shaft.

Full Floater:

There are essentially three ways to build a full floating 9″ rear. One way is to use a pressed-in spindle that is compatible with a Dana 60 hub. Another is to use a custom flange that mimics the bolt pattern of a Dana 60 knuckle. This allows a person to weld the flange to the end of the axle tube, and then bolt a traditional Dana 60 front spindle onto it. The last way is to adapt a unit bearing to the end of the axle tube. Spidertrax sells the components to do this and also sells F-350 unit bearings that have been re-drilled to many different patterns. In the case of a full-floating 9″ rear, custom axle shafts must be ordered. They have to be splined on both ends, and a drive slug is placed between the axle shaft and the internal splines of the hub.