Rear drum issues!!

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DPsuper
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Rear drum issues!!

Post by DPsuper » Tue Oct 18, 2016 4:08 pm

I have a 70 irs pan running wide 5 drums on the rear. A lug hole stripped out on me so I replaced the drum and when I go to tighten the axle nut down the drum will not turn. If I loosen the nut, just a little then it will turn fine. No grinding or anything like that when I spin the drum by hand. I left the nut just a little loose and drove it to make sure the new brakes I put on were working right, 20 miles later I need to replace the wheel bearing on the side that im having issues with. Now, im lost.

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Piledriver
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Re: Rear drum issues!!

Post by Piledriver » Tue Oct 18, 2016 11:01 pm

A not-fully-torqued axle nut can make the rear wheel bearings sound as if full of rocks.

IIRC the drums came in multiple widths, assuming dangerously you kept the old one, I'd be making some very careful comparative measurements.

A full set of press-in studs and lug nuts, or even just that ONE would be a better plan.
(The former better than the latter of course)
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

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Marc
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Re: Rear drum issues!!

Post by Marc » Wed Oct 19, 2016 12:21 am

Pre`68 5x205mm drums are compatible with 30mm wide shoes. They can be shoehorned over the `68-up 40mm shoes by turning the friction surface of the drum as far as possible - but even then it usually takes a spacer under the drum to eliminate drag. Totally Mickey-Mouse setup, when the drums overlie the linings it makes the drums much more susceptible to bell-mouth wear and fade. Many folks have done it, but IMO they're chuckleheads.

If you want to run "wide-5" wheels on a `68-up car you have a few options. Backdate to pre`68 brakes, switch to Type III/IV brakes using pre`66 Type III drums, or simply slip on some Thing drums (they'll fit over the `68-up brakes). The Thing drums do add to the track width, though, so if your fender clearance is tight they may not be an option.

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