Although the basic bigger is better and size matters points are still strong arguments in the wheeling community, there is more to the Ford 9" than its size.  The pinion is larger than the standard Dana 60, and that fact alone means more strength and less chance of damage.  The Ford 9" ring gear is also thicker (although smaller in diameter) than the Dana 60 ring gear, which again, means more strength and less worry. Ground clearance is another advantage to a 9", and a shaved 9" has even greater clearance, Click here to see a comparison.   Go to any NHRA, SCORE, NASCAR, or Local dirt track event and look under the rear of all of the vehicles. There is a reason drag racers and hotrod enthusiasts alike have trusted the Ford 9" for years, and here are a few of them.   
Note: despite its size, the Ford 9" system is lighter than the Dana system.

Left to right: Dana 30, Dana 44, Dana 60, Ford 9" pinions	On comparison of the pinions one of the first things you will notice is the additional pinion support extending from (in this picture) the lower end of the pinion.  This feature helps reduce the level of stress on the pinion. Note: the Ford 9" pinion enters the ring gear at a lower point, which also provides better strength and stability than the standard Dana 60.
The angle of the teeth on the Ford 9" pinion is at a greater degree than that of the Dana series.  This creates a larger contact area on the ring gear and greater tooth engagement; the area that stress is divided over is larger which means less stress on any particular area.	Left to right: Dana 30, Dana 44, Dana 60, Ford 9" pinions
Top comparison of main caps	The main caps in the differential are another strong point of the Ford 9" system.  They are the main link between the differential and the case on a Ford 9", or the housing and the case on a Dana.  Notice the difference in size and structure between the cast iron of the Dana and the forged steel of the Ford 9" main cap.
The modular design of the Ford 9" is an often overlooked advantage.  The main caps on a Dana design are an integrated part of the entire axle housing.  This means that if a Dana main cap fails, the whole housing becomes worthless.  The Ford drop out 3rd member (pictured below) contains the ring and pinion and the differential held in by the main caps.  If  the main cap fails you can replace the 3rd member and you are back on the trail.	Side comparison of main caps

Nodular Ford 3rd Member

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