The Underappreciated Drum Brake

I am referring to drums that have uneven internal diameter, usually with the outer friction area of the drum having a larger diameter than the area near the face of the drum.

You put new shoes in there and it really hurts your stopping ability.

There used to be a junkyard I would get drums from to keep my car going, old Smedly would try to unload bellmouthed drums on me, finally I started bringing my brake drum measuring tool and checking what he was selling me.

He then denied bellmouthed drums were a problem and that I should just put it on the car. I believe alot of these mechanics and parts peddlers had a devil may care attitude with drum brakes and that helped hurt their reputation.

:rofl:

Was that really the yard guy’s name?

Yes, his last name was Smedly. That’s a common name around here. We called him ‘ol Smedly, he could be a real rip if he was still hungover and would argue about the color of the sky when he was like that.

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Either buy new drums

Or turn yours

But don’t be a miserable cheapskate and buy junkyard drums

What the heck, @Old-Days-Rick

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This was in the 90s, back then all my vehicles had 4 wheel drums, I was poor and you could get a good quality drum at times from the yard for a great price, it usually worked out.

Unfortunately only one vehicle I own i s equipped with drums, the caprice has rear drums.

The brake drum needs to be resurfaced, “bell mouth” isn’t the problem as long as the drum is within service limits.

You are purchasing your brake parts from the wrong store. There is no point in buying brake drums that are worn worse than the drums on your car.

What do you expect from a salvage yard? You are buying scrap metal, use your own judgement when selecting used parts.

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Here’s another early disk brake design. Sort of a disk/drum hybrid.

Self energizing and enclosed like drums, fade resistant like caliper disks.

Ultimately too expensive, heavy, and complex for cars:

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Arguably, the greatest brake ever designed was the 8 luggage drums tgat came on Pontiacs in the 60s. Its as if someone was tasked with taking the overall best design, the drum brake, and making it without question the best brake without any of the shortfalls (real or perceieved) of the standard drum brake.

I have never had the pleasure of driving an 8 luggage car, but I have inspected a drum from one and they engineering marvels.

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The thing about the self energizing drum brake is it does an amazing thing, it self energizes. Absolute brilliant design.

Are those the “7 words you can’t say on television”? :rofl:

A design abandoned, never to be seen again. So all the world’s brake designers must be pretty ignorant.

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It was abandoned due to cost and Chevy didn’t want Pontiac to outperform the precious Corvette. Same reason they killed off the Fiero.

I don’t think a Bonneville will outperform a Corvette, those brake drums were used on full-sized cars.

What about other vehicle manufactures using that type of brake drum? The patent must have expired years ago.

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:joy::joy: The Fiero killed off the Fiero. :joy::rofl:

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My brother drove a Fiero for a few years. Fun to drive? Yes! But completely impractical. Only 2 (small) seats. My brother was over 6 foot. He said his head always hit the roof. Absolutely no carrying space. I remember when he moved from NY to Jacksonville for a job, his Fiero looked like those 3rd world trucks that are always overloaded!

The engine was the GM “Iron Duke”, a 2.5 L pushrod 4 cyl. They used that in lots of cars. My 1st new car was a 1988 Olds Ceira with the “Duke”. Good reliable engine but boring!

The last model year for the Fiero they offered a V6, huge improvement. Then GM did what they always do after really developing a car, they canceled it.

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The Fiero was in a much lower price class than the Corvette, so it wasn’t directly competing with the 'vette.

The Fiero quickly developed a bad reputation, due to the tendency for a connecting rod to go through the side of the engine block. And, many/most of the cars with that catastrophic type of failure also caught fire. Fieros were catching fire at the rate of one for every 508 cars sold, surpassing all other mass-market automobile cars.

The cause of these problems was traced to defective rods and also to the fact that the Fiero’s oil pan capacity had been reduced to 3 qts–which was barely adequate to begin with–and if a Fiero owner wasn’t careful to check and refill the crankcase on a regular basis, it was possible for the engine to be running with only ~2 qts of oil. One of the later “improvements” was to increase the oil pan capacity to 3.5 qts.

Little by little, the Fiero’s problems were lessened or resolved, but the damage had already been done by GM’s policy at that time of releasing models for sale before they had been adequately tested for reliability/durability.

By its final year of production, they were only able to sell ~27,000 units, so it was dropped from production.

I remember from all the Fiero’s I drove (customers) the 4cyl’s were anemic but handled great, then GM added the V6 and now it how power, but didn’t handle good anymore


Happened to my neighbor. Lost the car and did some good damage to his garage. Fire department showed up in time to save his house.

The Fiero had the same anemic engine (2.8l) I had in my GMC S-15 Pickup. I guess it worked fine in the Fiero because it was so light. But it was a real dog in my GMC pickup mated with the 5-speed manual. Traveling at 60 and even the slightest uphill grade and I’d to shift into 4th. Later GM introduced the 4.3l. And believe it or not it got better gas mileage then the 2.8 because you (or the automatic) didn’t have to shift to a lower gear for the slightest hill.

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I always understood that the 1989 Fiero was designed in such a way it was getting really close to Corvette performance and handling, so It got axed. The 1988 Fiero GT was one good looking car with performance to match.

And look at the new Corvettes! They made a new Fiero by a different name.

There’s no comparison of the new Corvettes to the Fiero except they both had mid-engines. Performance and handling isn’t even close.

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