Tapered Rear Axles
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automobile technology.
If, while attempting to apply any of the ideas,
procedures or suggestions herein, you should experience any kind of
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Those who pursue the Forward Look Mopars and some early 60's Mopar iron might have a special place in their hearts for the old tapered axle 8-3/4 rearend. That or they cringe at the sight of one. Our 63 Dodge is my first tapered axle bomber so I decided to dive and see for myself what's behind the love/hate relationship of a tapered axle mopar.
The example car I used is a 1963 Dodge 330 station wagon. It's engine was already removed, so we did not have the luxury of a driveshaft and a transmission in gear to keep the pinion from turning. To pull each side, the opposite wheel and the pinion must be secured. We secured one wheel by leaving it on the ground and we secured the pinion by placing a hydraulic jack under it and jacking it up under the yoke until some of the weight of the springs was holding the yoke tight against the floor jack (we tried a number of things prior to this...) The side of the car with the axle which we were removing was safely secured with some large jack stands. The drum looked like this before we got started.
We first removed the cotter pin from the axle and the castle nut and washer. On our Dodge, this was a 1-1/6" bolt and required a breaker bar to get it moving. Once the castle nut was removed, the wheel puller was installed. Our wheel puller was 30 years old or so and hadn't been used in 20 years. This is the puller installed on the wheel.
With the opposite wheel and the pinion secured, we started turning the
puller's screw clockwise. This meant lots of swings of a sledge
hammer. Those suckers were on there tight!
With the drum
off,
the taper of the axle and brake innards were revealed.
B
The drum and hub sat to the side.
Once we pulled the drum off, we reinstalled it with the castle nut but we did not tighten the nut down. It was installed just tight enough so we wouldn't need the puller again. We then re-installed the tire/wheel and set that side back on the ground so that we could work on the other side. Once we had the other side's drum and hub pulled, we put both sides up on jack stands.
On Mopar tapered axle cars, the brake backing plate carries the outside bearing seal. Once the brakes are disassembled (including the brake line to the wheel cylinder), the backing plate came off with five nuts. Behind the backing plate are the shim spacers that are used to adjust the load on the bearings (our wagon came with two on the driver's side and one on the passenger's side). Here is an image of the backing plate removed and two shims sitting on the taper of the axle.
Nice Trick: If you are removing the emergency brake cable in order to completely pull the backing plate off the car, use a small hose clamp to tighten and pull in the tabs that lock the cable to the backing plate. See Picture.
To finally remove the axle from the housing, we used a box-end 3/4" wrench faestened to the axle with the washer and castle nut. With several hard strikes to the wrench, the axle came out of the housing. The same procedure was followed on the other side. Of course, the factory shop manual describes using a special puller, if you have that, use it!
Now the axles are out!! Do you really want to put them back in? Here is a picture comparing an early splined axle with a later flanged axle. The later is preferred for its ease of removing and installing.
On our project, we had every intention of replacing these tapered axles with some 65 and later flanged axles. The set we had ready to test fit came out of a 70 Superbee (62-70 B-bodies all used the same width rearends, or so I thought...).
As you can see from the picture, the tapered axle is approximately 1"-1.5" shorter than the 1970 B-body axle.
The flange to flange measurement of the 63 B-body rearend is 53-1/4". Curiously, the same measurement on an A-body is 52-1/2", a sanct 3/4" narrower.