Here ya go... Dana 44 RS is what we are talking about. Thanks Mr N for all this info!!!

This article was written to document the early years of Dana 44 Reverse Spiral Solid front axle. It also includes information on the regular Dana 44 axle to compare the two, it is even expending into some Dana 60 info. It will concentrate on the Ford front straight axle from the mid 60's and several other axles. Additionally this article should dispel some of the myths about the first front drive axle that Dana / Spicer built with a Reverse Spiral Gear Set. The Dana 44 Reverse Spiral axle will be refereed to as the Dana 44RS within this article.

Dana designed the first reverse spiral axle in the early sixties for Ford. Dana released the 44RS for production in January 1965. Early enough to possibly be under a few rare 1965 F100's, however no written confirmation on this has been found. The 44RS was a complete new design in axle, with special design to lube the pinion that was above the fluid level. This axle has also been called the Dana 44 High Pinion, Dana 44 Reverse Rotation, Dana 44 Reverse Cut, Dana 44 High clearance and many more names. A reverse spiral axle has the center line of the pinion contacting the ring gear above the center line of the axle, and thus has different lubrication passages. This axle offers a strength increase over a standard rotation axle while in forward movement. It allows the drive shaft to contact the pinion yoke at a much higher level of connection, thus keeping the drive shaft several inches higher. The gears are not interchangeable with gear sets that are designed with the pinion below the centerline of the ring gear, however the carrier is. Reverse Cut refers to the direction the ring gear is cut for reverse spiral housing. The axiom of the reverse cut is to strengthen the gear while in the front drive axle of operation. Standard cut gears can not be swapped with reverse cut gears, however in the Dana 44 the ring gear carrier can be swapped. High pinion, Hy-Pinion or Hi-Pinion are all slang used in and out of the industry for a reverse spiral axle. High Clearance is a Ford marketing term used for the reverse spiral axle. Reverse rotation: is the single most misused axle term. Reverse Rotation is a slang term used to describe a reverse spiral cut housing. Neither the axle nor the axle shafts travel in a reverse motion, or travel 'backwards' compared to a regular housing. This term only shows the ignorance of the person or company using it.

In 1966 Spicer supplied this revolutionary Reverse Spiral axle, the Dana 44RS, for the new front coil sprung suspension on the Ford F100 4x4. (Picture 1 - 4.) The axle debuted with 3.54 or 4.09 gears, drum brakes, open king pin knuckles and running Spicier 5-260x U-joints. These axles were built in the Fort Wayne Indiana plant, even during the days of Edgerton. Spicer produced this style for Ford until the middle of 1971.

1971 was a year of change for this axle, the new axle now came with ball joints instead of king pins to hold the knuckles on. It still had 2 3/4" axle tubes with ½” thick walls and the 5-260 U-joint, with coil mounting brackets in 4 separate cast pieces welded at the top and bottom. The Panhard bar was still attached with a separate bracket, the axle stayed this way thru 1972.

1973 big change was to the larger 5-297 u-joint. It still came with ball joints, 2 3/4" axle tubes with ½” thick walls and the Panhard bar was attached with a separate bracket. The axle stayed this way thru 1975 on all F100’s & F150’s. The 1973 model year also saw the release of the 3.73 and 3.50 gear set in June.

In 1976 the axles coil mounting cast brackets were slightly changed. The front passenger’s side was made with the Panhard bar attachment cast in to it. Additionally 1976 was the first year Ford offered disk brakes as a standard option, although several late 75's have been rumored to have disks. This axle stayed the same for 1977 for the F100 and F150. The 1976-year also saw the release of the 3.00 gear set in December.

In 1977.5 Ford’s new F250 axle now started to appear. Previously, the F250 ran a standard rotation closed knuckle axle (see reference pictures below.) This axle for the F250 44RS is slightly different than the F100 & F150 offered in 1977. The F250 is a little wider than the F100 & F150, for the wider 8 wheel bolt hub. The F250 also has 3" wide axle tubes with ½” thick tube walls, and the axle has many different small changes from the F100 & F150 to include larger brakes. This axle stayed this way until it changed to the Twin Traction Beam (TTB) IFS system of the 1980 model year.

In 1978 the 44RS had its largest change to date for the F100 & F150, which stayed with the axle until the transformation to IFS in 1980. Spicer changed the coil mounting brackets from separate cast brackets that held on the radius arms to a new design that was a single piece per side, with the tubes pressed into the ends of the casting. The center of the cast pieces does not have a tube that passes through it! (See Picture 14) Instead, a tube is pressed on both ends and welded together. This system came with outer tubes 3/8” thick and center tubes 3/8” or ¼” thick.