Dana Rear Axles
Several models of Dana rear axles are used in regular production or are available as options on the E-250-E-350 and F-Super Duty Vehicles.
The Model 60-1U semi-floating rear axle is used on light duty E-250. The Model 60-1U full floating rear axle with single rear wheels is used on heavy duty E-250 and E-350. The model 70-1 HD and 70-2U full floating dual rear wheel axle are found on E-350. The Model 80 full-floating, dual rear wheel axle is used on F-Super Duty vehicles.
The pinion gear and shaft is supported by two opposed tapered roller bearings which are assembled in the forward side of the carrier housing. Pinion locating shims, installed between the rear bearing cup and the cup seat, control the drive pinion depth adjustment. The pinion bearing preload is controlled by shims located between the pinion front bearing and the shoulder on the drive pinion shaft.
The differential case assembly is supported by two opposed tapered roller (side) bearings and cups, which are retained in the housing by removable caps. Shims, installed between each differential side bearing and the shoulder on the case, perform three functions: they take up the differential case side clearance; they adjust the backlash between ring gear and pinion; and they establish differential side bearing preload. All Model 60, 70 and 80 Rear Axles have spacers outboard of the differential bearing bore to protect the housing if the bearing cup has spun in the housing.
A cover on the rear of the carrier housing provides access for inspection, removal and installation of the differential assembly and drive pinion. A metal tag, stamped with the gear ratio, part numbers and limited slip (if applicable), is secured to the housing by two of the cover bolts.
The Model 60-1U rear axle has semi-floating axle shafts, meaning the axle shaft supports the load.
The Model 80, 70-1 HD, 70-2U and 60-1U rear axles are equipped with full-floating axle shafts, meaning that loads are supported by the axle housing. The axle shafts can be removed without disturbing the wheel bearings, which are opposed tapered roller bearings and are part of the hub assembly.
The rear hub and rotor assembly on the Model 80 axle is supported or "floats" on the axle spindle on two opposed tapered roller bearings. It is retained on the spindle by a ratcheting nut that is tabbed to a slot on the spindle. If, for any reason, the hub is removed from the spindle, the old hub seal must be removed and a new hub seal installed.
The Dana Model 80,70, and 80 rear axles have an integral type housing; hypoid gear design with the centerline of the pinion set below the centerline of the ring gear.
The hypoid gear set consists of a ring gear and an overhung drive pinion which is supported by two opposed tapered roller bearings. Pinion bearing preload is maintained by the pinion nut and selective shims assuring the seating of the inner and outer bearings and cups.
The housing assembly consists of a cast center section with two steel tube assemblies and a stamped rear cover. The cover uses Silicone Rubber E7TZ-19562-A (ESL-M4G273-A) or equivalent as a gasket.
The differential case is a one-piece design with two openings to allow for assembly of the internal components and lubricant flow. The differential pinion mate shaft is retained with a threaded bolt lockpin assembled into the differential case.
Functional differences between the semi-float integral rear side assembly and the full-float integral rear axle assembly are as follows:
1. The semi-float axle shafts are retained in the axle by C-washer locks positioned in a slot on the axle shaft splined end. These C-washers also fit into a machined recess in the differential side gears within the differential case.
2. The full-float axle shafts are retained by bolts attached to the hub. The hub rides on two bearings at the outboard end of the axle tube.
3. A semi-float axle shaft rides on one straight- roller bearing at the outboard end.
4. Differential bearing preload and ring gear backlash are adjusted by the use of shims located between the differential bearing cup races and the carrier housing in the semi- float and the full-float axles.