Packard Forum Index » Post-War (1946-54)

I recently replaced the brakes on my '48 Custom with the Kanter kit -- shoes, cylinders, springs, master, hoses. The old shoes were not anywhere close to worn out but everything was old and one of the cylinders tended to stick so I opted to just replace everything.

I cleaned the backing plates and put a very thin film of ceramic high temp brake grease just on the contact pads for the shoes. The drums are in fine condition with smooth surface.

Everything went well for the first couple of short drives, but then the left front wheel began squealing loudly whenever the brakes are applied more than very lightly. I pulled the wheel off again and all looks fine except that the shoes do not appear to be contacting evenly. The ends of the secondary shoe, especially the upper, show some wear with none in the middle. The shoes are clean.

The other three wheels aren't making noise. Ideas?

A good brake shop, if such a thing can be found in your
locale would be able to match the radius of your shoes to the
drum. It should help.

Also, since the wear is only on one end of the shoe, a
"major adjustment" involving the center pivot might do
more good than anything.

Hi Rebus:

Those old brake drums need oversized linings.

Thus, you need to take/send the shoes and drums to a place like Fort Wayne Brake and Clutch to have linings cut to match.

That probably is not what is causing the squeal however. In fact squeal is still not very well understood. They just guess at what they think will not squeal and test it.

I knew a MOBIL engineer who said filing a chamfer on the edges of the shoe would get rid of squeal. He did it on his Packards in the 50's. Also some of those drums have srings on the to reduce squeal. If yours had them and they are gone that may cause a problem. They may also be squealing because old shoe material imbedded in the drum is transferring to the new shoes and causing a glaze.

Hope this helps.

I have new non-asbestos front linings on the Carib and they squeal more than the old asbestos linings, nature of the beast I'm told. It was pretty much minimized by keeping a tighter adjustment to the drum (after the shoes were arc ground to match the drum diameter). But as has already been suggested, adjusting the eccentric anchor pin is the most neglected part of brake service and should be at the top of your list.

I checked the center pin on all four wheels as part of the adjustment following reassembly, ensuring the spacing between lining and drum is as even as possible. The drums have an inspection port for a feeler gauge.

There are no springs around the drum and no obvious provision for them. I thought those were intended to aid cooling, not for noise. I would think a spring would amplify noise, if anything.

I cleaned the linings on that wheel. There was already quite a bit of dust buildup due to the chattering shoes and they had turned from tan color to charcoal color. After cleaning them which restored the tan color the wear didn't look nearly as uneven as before they were cleaned. I haven't taken the car for a drive yet to see if it makes any difference.

I think the lining material is already at least partially chamfered at the ends but I'd have to look at them again to be sure. It may be only one shoe is or just the leading or trailing edges.

Scott

There are no springs around the drum and no obvious provision for them. I thought those were intended to aid cooling, not for noise. I would think a spring would amplify noise, if anything.

Rebus, given you comment (above) you might find this interesting, drum perimeter springs to prevent or minimize squeaks/squeals caused by drum resonance. This page from the 1934 Service Letters and this feature was used in 1933 thru 1936 on the power-boosted mechanical brake Senior cars.

Attach file:

---

  (165.12 KB)

I never stop learning here. I also assumed the spring was to aid cooling. My '41 limo has them.

When you did the initial brake job did you happen to look at the condition of the braking surface of the drum? Was there and discoloration or glazing to the surface. I normally will scuff the surface of the drum with emery paper to break up any glazing. Also are all the contact points on the backing plate smooth and even? I have experienced myself where a groove has been worn over time and has caused the shoe to cock nad not making proper contact. I hope this helps you.


Also the shoes that we offer are like packard originally designed them with chamfers on both end and as for the discoloration in the shoe after inspection that could be impurities picked from either leftover brake fuild or grease that has soaked into the braking surface of the brake drum.

Thanks
James

I thought of the springs too since I didn't remember seeing any on my car & figured something else was missing. What is interesting is they apparently were not used on the postwar senior cars. I don't have any called for on the 47 Custom and didn't find them called for on 22-23 series Customs either. They are used on the smaller chassis. Wonder what the difference might be that Packard felt only some cars needed them.