I have a buddy putting together a old dodge for a street strip truck. He is wanting to stay with the original 5x5.5 axle bolt pattern and came across a 1963 Chrysler imperial. These axles have a pressed on axle flange but other than that they seem to be the same as most 8 3/4s. Question is whether or not it is a good idea to use the bolt on flange type, are they prone to snapping off? I have seen guys say they don't use them but never heard of anyone having issues with one. A 63 imperial weighed 4800lbs with 340 horsepower/ 470lbs of torque. This truck weighs 3600lbs 345 horsepower/ 453lbs of torque. To me I think this axle would hold up fines since it makes less torque and weighs less. Any thoughts?
They won a lot of SS/A classes with that type axle. Other than a pain in the ass to work on brakes because you need a puller to get the drum assembly off they work fine. Most replace those axles with 65 model year and up to handle more horse power then they handled back when they were production to get away from shearing the tapered shaft keyway.
Pressed on? If you mean the tapered axle and hub that is keyed, I wouldn't hesitate. They held up in the early 60s 413s just fine in quick strip use, see Ramchargers.
interesting that Mopars didn't have any trouble with keyed hubs, but they're always coming apart on old Fords, Jeeps, Hudsons, etc .
Read a how to article, forget where. They removed the hub from the drum, pressed in new wheel studs and then used 65 drums. You can then put hub back on and remove drum normally
Yep, works fine. But if you're like me, a rear brake job is maybe once in a cars lifetime so, is it worth it? You'll need a puller to do the first brake job or the mod, then you have it for the next time, IF it's ever needed again.
I think the really slow taper on the Mopar has a lot to do with that. At least, in my memory, the others have a much more pronounced diameter change. I do know that the Mopars are the hardest to pull.
A properly designed joint never transmits torque through the key...it all goes through the press fit. Remember, some engines use a two piece crankshaft, with the rear crankshaft flange pressed onto the shaft, sending all of the engine’s output torque through the press fit. Typical design for newer engines with rear gear trains.
I had one in my 63 New Yorker with a 413 and it survived my dumb ass teenager years... The transmission, not so much.
Check out Dr. Diff on the web. Has everything for the 8 3/4. Got my spool, gears, axles, rebuild kit from them. Might have to get the wheel stud pattern redrilled. My stuff is hanging in there so far...
Yes sir, I was under the impression they were pressed on and so was he and that is why that nut is there. BUT what you are saying is that that nut just holds on the drum? If so then you just remove it and rebuild brakes etc and your good to go. Thank you for everyone for responding, it is a great help.
No, I didn't mean to imply that the nut holds the drum only. the hub and drum are riveted together and have a tapered internal bore that matches the tapered axle. there is also a key the locks the two together. The slight taper is what really keeps in together though, that and that big nut. very difficult to remove as it requires a special puller. However a lot of guys have cut the rivets to separate the drum from the hub for brake access with success. I don't see the need for that since rear brake service is rarely needed and I have a puller.
When I built the 1940 Dodge in the early 70's I used the 1962 Oz Chrysler rear axle.......with a keyway/tapered axle setup.....after I put 11" vented discs on the modified 1940 front end I decided the rear end also needed discs........ I removed the brake drum with the "coxhead" brand puller, knocked out the rivets holding the tapered hub to the drum, threw the drum away and had the hub edge/diameter machined a few thou to fit inside the separate 11" vented front disc 1" thick hat from an Oz 1970 Valiant .......used a couple of countersunk allen screws to hold the disc/hub together and installed Ford 1/2" UNF wheel studs through the both hub & disc then installed this assembly onto the tapered axle with a new key, castle nut and cotter pin & about 150foot lbs torque.............then cut the drum brake backing plate down completely to just hold the rear axle bearing & seal........then made up a caliper bracket to hold the Oz 1976 Ford rear disc caliper using four of the five axle flange bolts and I then had nice 4 wheel vented discs and the car stopped really well..........this setup lasted till the early 2000's when I replaced the whole rear end with one from a 1990's Oz Ford rear disc rear end but in 30 years never had an issue with that center nut or tapered axle hub.........but I did have a puller than never met a tapered axle that stopped it............lol...............andyd
I've not ever heard of the pressed-on rear crankshaft flange deal. Shoot me a couple examples so I can be educated.
As long as you have the proper wheel puller these rear axles should be fine ....Just remember the rear wheel bearing end play is adjusted with shims and not the threaded adjuster like the later rear axles...
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