A Dana is a Dana is a Dana no matter what vehicle it is mounted on.
The term "reverse rotation" and "reverse cut" are often mistakenly interchanged. Reverse rotation refers to the direction of the front differential gear motion when driving the vehicle forward and that is the way they worked prior to 1977. The differential redesign by Dana at Fords request changed the gear cut to a reverse cut and a differential design change the alowed the gears to turn on the strong side. The old design caused the gears to rotate on the weak side thus the term "reverse rotation" for the front differential.
Something that may be of interest is the term reverse rotation, from here on I quote information from the Dynatrac Corporation in an article written by one of their engineers by the name of Jim McGean. Unfortunately the article is no longer available online. I am considering contacting Dynatrac and requesting permission to reproduce the entire document, which covers a lot more information on Axle Swapping and Building. I am only quoting a few paragraphs that apply to the "reverse rotation / reverse cut confusion".
"Reverse-cut is often mistakenly refered to as reverse rotation. this is perhaps the single most misunderstood term by 4-wheelers and even a lot of people in the axle business. A reverse cut housing is not just like a standard cut housing turned upside down. It is a specially designed housing for front drive axles. Contrary to popular belief, id does not turn backwards or in reverse. The term reverse cut actually refers to the direction of the spiral cut in the ring gear. In a reverse cut axle the spiral on the ring gear is opposite from a standard cut ring gear. The idea behind reverse cut is to strengthen the operation of the gear when it is used for front driving axle operation.
Years ago when 4 wheel drive was invented, the front axle used the same gears and housing as an ordinary rear end. This was done for economic reasons since the components were already in mass production. They simply added the necessary parts to enable steeering. However, all ring and pinion gears are cut in such a way that they are inherently stronger when pushing the vehicle in a forward direction and weaker when driving in reverse. So that means the standard cut (rear-end style) gear when used in the front, must push on the weaker side of the gear to move the vehicle in a forward direction.
This practice continued until the late 1970's when Ford asked Dana to design a new axle that would be stronger for front axle use and also provide better driveline angles for shorter front drive shafts, then being used in new trucks. Dana responded by designing a new housing and reverse cut gear set with a pinion that entered the case above the centerline of the axle. Ford used this new approach in all their 4WD vehicles built from 1977 onward. Other manufacturers didn't start using this approach until the late 80's, and many still use the same standard cut, rear-end style design for front drive axle use.
The bottom line is that reverse cut gears (front axle style) and axle assemblies are inherently stronger for front axle use because of the way the gears mesh when moving the vehicle in a forward direction. They also provide better driveline angles because the pinion is located above the centerline if the axle.
The gearset used in each axle are not interchangable. Standard cut gears cannot be used in place of reverse vcut and vice versa. The housings are also not interchangable. However differential cases, be they open,posi, or locker are compatible with both styles, as long as the spline count matches the axle shaft. So you don't have to buy a special differential for either one."
The bottom line here is that front differentials on Fords prior to 1977 used a stndard cut ring and pinion which ran in reverse rotation when the vehicle was moving forward turning the gears on the weak side. From 1977 on Ford used the "reverse cut" design and housing that allowed the rotation to be on the strong side of the gears.
And that's Dynatracs story and I'm sticking with them
/ Hope I didn't bore ya :blush: Thought you might find that interesting. :blink:
Good luck,
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