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Axle nut torque:

The desired torque should be a function of the tread diameter and pitch. For the later cars both the 3/4 X 16 and 7/8 X 14 had a call-out of 200 – 270 ftlbs. If the ’37 has something smaller than 3/4 inch diameter then the later torque specification IMO would not apply. My ’35 – ’42 Motor’s Manual is silent on the subject as is the ’40 – ’54 version of the manual.

My tool handbook (circa ’49) lists the failure torque of a 3/4 -16 as 390 ftlbs, and 7/8 – 14 as 625 ftlbs. If the ’37 Packard has a smaller axle thread diameter/pitch of say 5/8 – 18 that failure torque is listed as 220 ftlbs. It would appear that Packard was comfortable pushing the fastener to about 70% of the failure torque for the junior cars, but the senior cars pushed only to 43% of yield. If you find the axle thread is 5/8 – 18 then consider 110 ftlbs (50% of 220), otherwise for the 3/4 -16 shoot for the low side of the later car specification 200 ftlbs (≈50% of 390). There was no mention of lubrication, so I’m assuming dry thread and washer surfaces in the above data.

I would ‘stone’ the nuts to get the cotter pin to fit versus ramping-up the torque.

dp

Technically accurate but I'm not sure that's totally true in this case as some of it would depend on the bearing type. Due to the relatively small contact area of ball bearings, too tight and bearings will be embedded into their seats.

Well the axle nut is used to seat drum onto the axle taper. So not sure how much that would effect the side load bearings. The bearings are pretty much fiction fit into the axle housing and then a spring washer and backplate hold everything in place.

The threaded portion of the axle shaft measure approx .860" so a tad less than 7/8ths. So 200 ft/lbs?

The rear backing plate was ugly. I was cleaning it up to paint and realized both the anchor pin eccentric and the rear shoe eccentric was rust frozen. It lots of penetrator and heat to even break them free of the backing plate. Thr pin adjusted is free and working.

But on the other eccentric, the little "wheel" that is supposed to spin as the rear shoe moves on is still frozen solid. It's currently soaking in a cup of PB blaster overnight to see if that will free it.

Otherwise, I make have to source a replacement eccentric. Hopefully the other side isn't as bad.

Also this is what I mean by the back passenger is unacceptable right now. If I needed to I could back the 54 out and then move the trashcans. But hopefully I won't have to.

The car almost looks like it just hovering.

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A video I did on using a drum puller since this gets asked a lot:

A kidneys worth of parts just arrived from the UK.

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I may be close to needing that custom casket after all as I thought we were talking about the front bearings. Not sure why I thought that as it would make no sense but obviously torquing the rear drums that much would make perfect sense.

Having said that, I don’t recall ever using a torque wrench on a rear drum nut (or on anything other than head nuts) although now that I have a better one that is more accurate and easier to use, I’ll likely do so from now on!

You really make progress.

When your done

Want to do my dads 12....!!

Hah...

I picked up a macker puller from stuff gerry bought.

Had to of been used on fire engine. Drums.

Its not a striker ..

And you are giving me guidance.. Since the bodies are about the same.

Thanks.

Kev:
7/8 inch diameter would suggest 270 ftlbs, but before I jumped into the deep end I would torque to 200 ftlbs plus whatever it took to get to the next castellation. And then recheck at 200 ftlbs in 100 miles. My concern is my ignorance on the pre-war materials and heat treating versus the post-war hardware.

I would also clean up the nut face and washer especially if they are heavily scored. I don’t know of any technical reason stopping you from just backing up if you over torque and miss cotter pin alignment the first time.

I’ve doubled checked and confirmed 100 ftlbs is appropriate for a 5/8 X 18 axle. That’s the Brand X configuration and it’s ben OK for some 95 years at that torque, so perhaps my concern about pre-war materials is unfounded.

I watched your video . . . I must get a Big Orange Hammer!

dp