Dana 70

The Dana/Spicer Model 70 is an automotive axle manufactured by Dana Holding Corporation and has been used in OEM heavy duty applications by Chevrolet, Dodge, and Ford. It can be identified by its straight axle tubes, 10 bolt asymmetrical cover, and a "70" cast in to the housing and is visually similar to the Dana 60. The majority of the Dana 70s are rear axles, however Dana 70 front axles do exist. Both front and rear axle variations were first offered in 1957. The Dana 70 is generally regarded to have more strength than a Dana 60 but not as much as a Dana 80. Gross axle weight ratings are often lowered by the vehicle manufacturer for safety and tire reasons.

In general, Dana 70 front axles are uncommon, due to attributes that the Dana 60 front axle can match. The main advantage a Dana 70 front axle has over a Dana 60 front axle is better gross axle weight ratings.

The first Dana 70 front axle was used in 1958 by Dodge in the W300, in both 4.88 and 5.87 ratios. International started using Dana 70 front axles in the late 1960s. Both companies used Dana 70 front axles until the mid-1970s (Dodge W300 pickup up until 1978, discontinued in 1979). All of these Dana 70 front axles were closed knuckle, with king pins and had a GAWR of 6000 lbs. Like the rear Dana 70 axles, the Dana 70 front axle started out with 23 spline axle shafts and then went to 35 spline axle shafts. While these axles were being manufactured, Dana offered a "Power-Lok" limited slip differential for some of these axles.

GM began making 4x4 Chevrolet Kodiaks and GMC Topkicks that utilize a Dana 70 front axle for the 2005-2009 models. These Dana 70 axles had open knuckles and ball joints. These Dana 70 axles only came with 5.13:1 gear ratios and had a GAWR of 8000 lbs. They differ greatly from previous Dana 70 front axles, some of the major differences being the use of 1550 Universal Joints and being a high pinion, reverse cut axle.

All Dana 70 rear axles are full floating and typically have a gross axle rating of 7500 lbs. The Dana 70 rear axle was first used in the Dodge W300 in 1958. The Dana 70 started out using 10 spline pinions and 23 spline axle shafts. The later, more current, Dana 70 axles use 29 spline pinions and 32 or 35 spline axle shafts. Dana offered two different limited slip differentials with the Dana 70, the "Power-Lok" and the "Trac-Lok."

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