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Kevin, it makes me so happy to see your energy, persistence and progress on this car.

Mark would be so happy to see all this. I feel that one of these days, he'll be in the background, peeking in on one of your photos.
Pat

The comment about the same springs is odd to me in that the parts books has two different springs for all 22nd to 54th series cars. Not the same spring for every series car, but for any one brake configuration there were two different springs. Having said that once the material is selected there are only a few characteristics that make one coil spring ‘stiffer’ than another. The wire diameter, number of coils, and mean diameter of the coils are variables that change the fundamental stiffness (pounds force per inch deflection). Since there is no reason to have different spring rates in a brake drum application I would bet the stiffness is the same for both the primary and secondary application. The only variable left is the initial preload which is determined by the difference between the installed and uninstalled length of the spring. The only difference between the two springs may be the uninstalled length . . . and not by a lot . . . maybe something like 1/8 inch.

If I was in the business of making brake springs I would advocate using the same stiffness (wire, coil count, outer diameter), and make the difference in the uninstalled length. In that way I could have my winding machines running full speed ahead, and manage filling purchase orders at the hook bending production step. Let’s not forget the different color paint. The ’54 shop manual associates an orange spring for the primary shoe, and a yellow spring for the secondary shoe. Some seventy years later I wouldn’t expect the supply chain to use the same Packard color codes, but if there is a difference in the springs I would expect two different colors . . . and that difference may only be the length . . . shorter is the secondary.

The artwork that Howard posted (bottom of page 209) shows the ‘extra’ spring on the secondary side, so if the ‘extra’ brackets are on the trailing half of the backing plate then I think those ‘extra’ springs are there to ensure the primary shoe moves first.

dp

DABID, 54 Seniors and Super Clippers used two different springs as you described. But the 54 Special and Deluxes used the newer smaller brakes/drums (same as 55 Clippers) and they went with two of the same spring. Why, I don't know.

Pat, thanks I appreciate it!

Got one side of the rears pulled apart. Boy, those were mucky. Lots of grease, rust and crud. Also, no way the axel nut was on to torque specs as that came off easier that the lugs nut did. But there was a cotter pin!

The rears also appeared to be painted an odd tan colors (inside and out) and painted over in black paint that melted away with the brake cleaner.

Pulled the rear backing plate off to get at the axle. Was expected a tappered axle bearing like on my 54. Not a sealed roller bearing. It still feels good, so I guess I'll roll with it. But inner axle seal as toast. So I'll have to replace those.

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Oil seals ordered. My local Advanced Auto will have them by Sat morning.

Kev, thanks for the correction . . . I must have misidentified your chassis number, and then worked upward in the parts listing, thus completely missing the last line. Even with all of the springs identical I could still get the primary moving first by having the hole in the shoe closer to the anchor. That would really confuse things by now having, in addition to shoe length, primary and secondary shoes with different spring hole locations, but the whole industry is driven by ‘lowest cost design wins’. Or perhaps the whole mess of primary and secondary shoes was overcome with better friction materials.

As far as I know the tapered rear bearing design with the thrust block was introduced with the ’38 JRs. In the land of Brand X low torque on the axle nut is believed to be a contributor to axle failures. In my ’48 Eight fatigue cracking started at many origins in the radius between the taper and threads, which lead to the wheel coming off, but thankfully the drum and shoes kept the wheel walking only about an inch down the taper. Perhaps with the axles ‘in hand’ you can give them a thorough inspection.

dp

Decided to replace the front axle seals as well. One side looked okay, the other side was an older leather seal that was a bit rougher. Figure while I have everything apart, I may as well replace them both with fresh seals so I don't have to go back in later if there is an issue.

$16 at my local NAPA, and they will be here tomorrow.

The only part I need to make is a paper gasket that goes between the rear backing plate and the "grease shield" piece.

I believe I had to make that similar part on my '54 as well.

Is there supposed to be some type of gasket between the rear backing plates and the axle housing? There wasn't evidence of one when I pulled this apart.

I found this on the front wheel bearing" "torque" specs. But, I cannot locate the rear axle nut specs. Are they similar to the Post War at ~200-250ft/lbs?

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If the 37 axle configuration is anything like the later ones I believe the only thing between the backing plate and axle housing would be some thin metal shims if any are needed for end play adjustment.

Note there is an interesting statement in the SM under 37 having non adjustable ball bearings and that is of a spring washer at the same location shims would be for later axles. Did you find anything like that?

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