Dana 70
Encyclopedia
The Dana/Spicer Model 70 is an automotive axle manufactured by Dana Corp.
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.
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.
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.
s and GMC Topkicks that utilize a Dana 70 front axle for the 2005-2009 models. These Dana 70 axles had open knuckles and ball joint
s. These Dana 70 axles only came with 4.88:1 or 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.
s with the Dana 70, the "Power-Lok" and the "Trac-Lok."
. However Ford still kept the Dana 70HD a option until the Dana 80
was made available. The axle was available or optional for the Big Three until 1994 when Dodge used the Dana 80 for its dual rear wheel trucks instead. The Dana 70HD is still seen in commerical applications today. In the UK the 70HD was used in a 10/23 spline version for the Ford A-series
truck with a European 6x205mm hub bolt pattern.
Dana Corp.
The Dana Holding Corporation is a supplier of axles, driveshafts, off-highway transmissions, sealing and thermal-management products, and service parts....
and has been used in OEM heavy duty applications by Chevrolet
Chevrolet
Chevrolet , also known as Chevy , is a brand of vehicle produced by General Motors Company . Founded by Louis Chevrolet and ousted GM founder William C. Durant on November 3, 1911, General Motors acquired Chevrolet in 1918...
, Dodge
Dodge
Dodge is a United States-based brand of automobiles, minivans, and sport utility vehicles, manufactured and marketed by Chrysler Group LLC in more than 60 different countries and territories worldwide....
, 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
Dana 60
The Dana/Spicer Model 60 is an automotive axle manufactured by Dana Corp. and used in OEM "heavy duty" pickup applications by Chevrolet, Dodge, Chrysler, Jeep and Ford. There are rear axle and four wheel drive front steering versions of the Dana 60. It can be readily identified by its straight axle...
. 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
Dana 60
The Dana/Spicer Model 60 is an automotive axle manufactured by Dana Corp. and used in OEM "heavy duty" pickup applications by Chevrolet, Dodge, Chrysler, Jeep and Ford. There are rear axle and four wheel drive front steering versions of the Dana 60. It can be readily identified by its straight axle...
but not as much as a Dana 80
Dana 80
The Dana/Spicer Model 80 is an automotive axle manufactured by Dana Corp. 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 "80" cast in to the housing. Dana 80's are made as full...
. Gross axle weight ratings are often lowered by the vehicle manufacturer for safety and tire reasons.
General specifications
- Ring gear measures 10.5".
- 3.5" diameter axle tube.
- Inner axle shaft spline counts are 23, 32, and 35
- Pinion shaft diameter: 1.75"
- Pinion shaft splines: 10 and 29
- Gear ratios: 3.07:1 - 7.17:1
- Axle Shaft diameter
- 1.41” Front (35 Spline)
- 1.50” Rear (35 Spline)
- Axle spline diameter
- 1.50” Front (35 Spline)
- 1.50” Rear (35 Spline)
- 1480 Universal Joint (Front axle)
Front axle
In general, Dana 70 front axles are uncommon, due to attributes that the Dana 60Dana 60
The Dana/Spicer Model 60 is an automotive axle manufactured by Dana Corp. and used in OEM "heavy duty" pickup applications by Chevrolet, Dodge, Chrysler, Jeep and Ford. There are rear axle and four wheel drive front steering versions of the Dana 60. It can be readily identified by its straight axle...
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.
Dodge and IHC Dana 70 front axles
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. All of these Dana 70 front axles were closed knuckle, with king pins and had a GAWRGross axle weight rating
The gross axle weight rating is the maximum distributed weight that may be supported by an axle of a road vehicle. Typically, GAWR is followed by either the letters FR or RR, which indicate front or rear axles respectively.-Importance:...
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
Limited slip differential
A limited slip differential is a type of differential gear arrangement that allows for some difference in angular velocity of the output shafts, but imposes a mechanical bound on the disparity...
for some of these axles.
GM Dana 70 front axles
GM began making 4x4 Chevrolet KodiakChevrolet Kodiak
Beginning with the 2003 model year, US-market models moved to a new platform with a more spacious cab based on the GM full-size vans. The 4500 and 5500 trucks had the option for Four-wheel drive. These trucks featured solid front axles, on both 4x2 and 4x4, instead of independent front suspension...
s and GMC Topkicks that utilize a Dana 70 front axle for the 2005-2009 models. These Dana 70 axles had open knuckles and ball joint
Ball joint
In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles.More specifically, a ball joint is a steel bearing stud and socket enclosed in a steel casing. The bearing stud is tapered and threaded. It fits into a tapered hole in the steering knuckle. A...
s. These Dana 70 axles only came with 4.88:1 or 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.
Rear 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 differentialLimited slip differential
A limited slip differential is a type of differential gear arrangement that allows for some difference in angular velocity of the output shafts, but imposes a mechanical bound on the disparity...
s with the Dana 70, the "Power-Lok" and the "Trac-Lok."
Dana 70HD
In the 1970s the Dana 70HD was offered. The axle tubes and carrier bearings were larger and thicker, the axle shafts were 35 spline only. These upgrades gave the Dana 70HD a gross axle rating of 10,000 lbs. The Dana 70 front drive axles used in the Chevrolet Kodiaks and GMC Topkicks also had these features. This axle was standard for the Big Three (automobile manufacturers) dual rear wheel trucks until 1985, when Ford started using the Sterling 10.5 axleSterling 10.5 axle
The Sterling 10.5 axle is an automotive axle manufactured by Visteon at the Sterling Axle Plant in Sterling Heights, MI. It was first used in model year 1985 Ford trucks. The axle was developed to replace the Dana 60 and Dana 70...
. However Ford still kept the Dana 70HD a option until the Dana 80
Dana 80
The Dana/Spicer Model 80 is an automotive axle manufactured by Dana Corp. 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 "80" cast in to the housing. Dana 80's are made as full...
was made available. The axle was available or optional for the Big Three until 1994 when Dodge used the Dana 80 for its dual rear wheel trucks instead. The Dana 70HD is still seen in commerical applications today. In the UK the 70HD was used in a 10/23 spline version for the Ford A-series
Ford A-Series
The Ford A-series was built in the UK from 1972 to 1984 to fill the gap between the relatively small Transit of 3.5 metric tonnes GVW and the bigger 7 tonne D-series....
truck with a European 6x205mm hub bolt pattern.
Dana 70U/Dana 70B
In the 1980s the Dana 70U or Dana 70B was offered. GM, Ford and Dodge all used this axle. This axle had a smaller pinion bearing and mostly have 32 spline axle shafts. The Dana 70U and Dana 70B both have gross axle weight ratings of 7500 lbs. The 2nd generation Dodge Ram trucks consistently feature this axle in the 2500 trucks with the Diesel or V10 and automatic transmission. This axle was designed for single rear wheel applications.Pinion Offsets
There are three pinion offsets for the Dana 70 rear axle. 1/2 inch, 5/8 inch and 31/32 inch offset. The first Dana 70 axles had a 1/2 pinion offset and were found in Dana 70HD's as well. The drawback with the 1/2 inch offset was that a 4.10:1 gear ratio was the highest gear set possible. In the 1970s the 1/2 inch offset was phased out for a 5/8 inch offset that allowed for higher gearing. The 5/8 offset was used in all the major variations of the Dana 70 and is still being used today. A 31/32 inch offset was used for a short time in the late 1980s to the early 1990s to allow even higher gears than the 5/8 offset could offer. Only the Dana 70-3HD used the 31/32 inch offset.External links
- http://77cj.littlekeylime.com/Dana70.htm
- http://www.ringpinion.com/DiffList.aspx?SearchMode=Diff&TypeID=3
- http://www.pirate4x4.com/tech/billavista/D70/D70.htm
- http://www.off-road.com/trucks4x4/article/articleDetail.jsp?id=186511