Dana/Spicer Model 70-1HD &70-2U

NOTE: When changing ratios on Dana/Spicer Model 70-1HD, and 70-2U series axles, it may be necessary to change the differential case, ring gear and drive pinion.

Fig. 3 Exploded View Of Model 61-1U, 70-1Hd & 70-2U Full-floating Rear:

1. Remove axle assembly from vehicle. Service and Repair
2. Remove axle shafts.
3. Remove cover plate and drain lubricant, then clean all gasket surfaces.
4. Remove bearing caps. Note matched numbers or letters stamped on the cap and carrier assembly. These numbers or letters must be matched during assembly. These numbers may either be stamped vertically, horizontally or, in some instances, both vertically and horizontally.
5. Mount spreader tool No. 4000-E, or equivalent, onto carrier assembly.
6. Position a dial indicator onto carrier, then spread housing.

CAUTION: Do not spread housing more than 0.015 inches.

7. Remove differential case from carrier. It may be necessary to pry case from carrier with suitable pry bars. Use care to avoid damaging machined surfaces.
8. Remove and tag bearing cups to indicate which side of carrier they were removed from, then remove spreader tool from case.

NOTE: Model 70 series axles use spacers installed outboard of each bearing cup, remove and tag for reference during assembly.

9. Remove differential case bearings from case using tool No. D81L-4220-A, or equivalent. Place tool in a vise when removing bearing. Turn case over and remove other bearing in the same manner.
10. Wire shims, bearing cup, bearing, and spacer, if applicable, together and identify from which side of differential case they were removed. If any shims are damaged, replace with new shims. It is recommended that bearings be replaced.
11. Place a few shop towels over a vise to prevent ring gear teeth from being nicked after it is free from case assembly. Remove ring gear bolts, leaving four bolts loosely assembled 90 degrees apart. Tap each bolt head alternately with a rawhide or plastic hammer to loosen ring gear from case. Remove case and ring gear from vise.

NOTE: If applicable, use care not to damage exciter ring when removing ring gear. Whenever removing ring gear bolts, discard and replace with new bolts upon assembly.

12. If applicable or necessary, remove exciter ring using a soft faced hammer, then discard ring.
13. Replace differential case in vise, then drive out lockpin that retains pinion mate shaft to case.
14. Remove pinion mate shaft using a suitable drift, then rotate side gears until pinion mate gears turn to opening of case.
15. Remove pinion mate gears and spherical washers behind gears, then lift out side gears and thrust washers.
16. Inspect all parts, including machined surfaces of case. If any one of gears are to be replaced, they are to be replaced as a set.

NOTE: If excessive wear is visible on all parts, it is suggested that complete differential case assembly be replaced.

17. Turn nose of carrier upward, hold end yoke or flange with a suitable pinion flange holding tool, then remove pinion nut and washer from pinion shaft.
18. Remove end yoke or flange using a suitable yoke remover and inspect. If yoke or flange shows any signs of wear, replace.

Fig. 5 Exploded View Of Pinion Preload Spacer & Shims. Model 70 Type Full-floating Rear Axle:

19. Remove drive pinion by tapping on drive pinion shaft using a rawhide or plastic hammer. Catch pinion to prevent damage to pinion teeth. On spline end of pinion there are bearing preload shims. Collect shims and keep together for reassembly.

NOTE: Model 70 axles may also use a pinion preload spacer with preload shims, preload spacer must be assembled in sequence or unit failure may occur.

WARNING: Gear teeth may have sharp edges, use care when handling gear to prevent personal injury.

20. Remove drive pinion oil seal from carrier using a suitable bearing cup puller and a slide hammer.
21. Remove outer pinion bearing cone and outer oil slinger.
22. Turn nose of carrier downward and remove outer pinion bearing cup using a suitable pinion bearing cup remover and driver handle. Locate driver on back edge of cup and drive cup out of bore.
23. Remove inner pinion bearing cup and baffle using a suitable pinion bearing cup remover and driver handle. Shims are located between bearing cup and carrier bore and may also include an oil baffle. If shims and/or baffle are bent or nicked, replace. Wire shim stacks together and measure each. If stack has to be replaced, replace with same thickness.
24. Remove inner pinion bearing from drive pinion using tool No. D81L-4220-A, or equivalent.