Why is drum to disc called an upgrade?

[dmjlambert]

I'm just curious. Why is drum to disc brake conversion called an upgrade by so many people? Is it just because later model trucks happen to be made with disc brakes so people assume it is better? Has that ever been demonstrated? Did disc brakes come about because they were cheaper to make and less complicated for maintenance? Or because they are actually better in some other way? I know disc can cool down better if subjected to extreme use, so I suppose if I lived in the mountains there may be a slight advantage with disc. Anything else? I was just wondering if the upgrade idea is something that is not real but gets passed around, like having distributor gear engaged some number of teeth off that supposedly could affect timing.

[bill3rail]

Have you driven a four wheel drum vehicle? Disc is definitely an upgrade in performance and ease of maintenance.

Just my .02
Bill

[68 P.O.S.]

One reason is drums do not cool as well as discs. Drums heat up and fade out real easy with lots of use, especially when towing and going down steep grades. Front way more than the rears

[Ironhorse]

Besides the drum brake fade with use, ever try stopping with wet drum brakes if having gone thru water entering the brake drums? Stopping distance with wet drum brakes is greatly reduced, much more than wet disc brakes. Drums with hydraulics are much better than the old pure mechanical brakes but the discs do out perform the drums also. Just my .02 worth.

[54blackhornet]

Is this an early April Fools Joke ?

[ZEKE68]

Stopping when its raining and the roads are wet is a lot less exciting with disc front brakes. This was the biggest surprise I had when I bought this truck with four wheel drums. It had been decades since I had had four wheel drums, so I had forgotten. The drums do not apply as evenly as disc brakes do.

[Stocker]

A nice big pair of drums on the rear will do a great job as a parking brake. Other than that, IMHO discs are better in every way, especially up front. Some will say that a well-adjusted drum setup works just fine, and if it works for them, that's fine with me. But after 50+ years of driving and several vehicles with drum setups, I'll take discs any time, for reasons posted above.

[KQQL IT]

Originally Posted by bill3rail

Have you driven a four wheel drum vehicle? Disc is definitely an upgrade in performance and ease of maintenance.

Just my .02
Bill

200% better

[bill3rail]

Originally Posted by ZEKE68

. The drums do not apply as evenly as disc brakes do.

Maybe not perfectly even but mine are adjusted real damn close to perfect. I do not change lanes unexpectedly when braking hard which is a sign of improperly adjusted brakes.

Bill

[special-K]

It's ok to ask. Discs are an upgrade in maintenance as well as performance. They were a performance upgrade on the '60s-'70s muscle cars. They were first used on race cars. I guess that's what's on airplanes.

[dagnabbitt]

Four wheel drums were fine when everyone was running them.

The problem nowadays is that if you are running drums in heavy traffic or in poor conditions you might feel safe, if you are attentive. Well, just wait until someone with discs cuts you off and then slams on the brakes one car length in front of you.

My 1970 still has four drums and I keep saying to myself, would you people see what I am driving, does it look like it stops on a dime? But new drivers who are cutting you off don't think that way, they assume everyone can stop as fast as they like.

[Steeveedee]

Disc brakes use the pads to continuously wipe the rotor so that there is less likelihood for poor performance when it's wet out. Also, they clamp the rotor as opposed to pushing outwards on a drum. In the case of thermal expansion of the rotor, braking performance is not diminished. In the case of drums, the thermal expansion of the drums causes more pedal travel as the drums heat up. Disc brakes are also self-adjusting.

Let me just ask the question- Since drum brakes are cheaper, why are all manufacturers required to supply front disc brakes? They cost more. Disc brakes are on there for performance reasons. This is a "tastes great, less filling" argument that you will see all over the internet, and the fact is that front disc brakes have more, and safer, stopping power.

[KQQL IT]

Originally Posted by bill3rail

Maybe not perfectly even but mine are adjusted real damn close to perfect. I do not change lanes unexpectedly when braking hard which is a sign of improperly adjusted brakes.

Bill

You dont have to adjust disc brakes.

[68panelman]

We all know disc is better, that's why all the high performance cars got them in those days. Both my trucks are all drum systems I'm so used to them they don't bother me, and I can tell you one thing, they definitely make you a better, more conscientious driver

[Red71gmc]

Originally Posted by dagnabbitt

Four wheel drums were fine when everyone was running them.

The problem nowadays is that if you are running drums in heavy traffic or in poor conditions you might feel safe, if you are attentive. Well, just wait until someone with discs cuts you off and then slams on the brakes one car length in front of you.

My 1970 still has four drums and I keep saying to myself, would you people see what I am driving, does it look like it stops on a dime? But new drivers who are cutting you off don't think that way, they assume everyone can stop as fast as they like.

This is a very true statement. When everyone had old style brakes they drove completely different and realized others couldn't stop on a dime.
Apparently there are still some vehicles without power steering because I don't know how many times I about had my left front side swiped when people shave a left turn. Or is that just me?

[CaptRMW]

Mr. Lambert I will invite you to take a test ride with me. Be sure to fasten your seat belt or I will pile your butt up on the dash with my drum disc with semi-metallic shoes and pads on all four. Drums are fine with newly turned drums and new quality shoes but the stopping power diminishes at a fairly rapid rate compared to discs with miles driven. I have driven my share of miles with 4 wheel drums and I can tell you a panic stop at 70 miles per hour will likely make some skid marks but not on the asphalt.

[davepl]

Drum or disc, I still spend a lot of my time in traffic managing the gap in front of and (to the extent I can) behind me. Maybe it's because I'm 50 or because I spent five years hand-restoring this truck and don't want it hurt, but I drive pretty darned paranoid.

Your biggest risk is the car in front of you stops suddenly, and then you're sideways in a four wheel drum lockup. So drum OR disc, I leave lots of room so that doesn't happen.

But I too upgraded fronts to disc! And I no longer own a front drum vehicle. Drums stop pretty good when dry the first time and when properly adjusted and new.

[S_Gibson]

I just ran new lines to the rear of my truck, because i could not "Lock Up" the brakes no matter what I tried. The rear hose was old and swollen. Now I can easily stop and "Lock Up" the brakes. I have yet to drive in wet conditions so I'm not sure how 4 wheel drums will. The performance I've notice thus far seems comparable to disc on every other vehicle I've owned, but I've not been on any road trips or drives longer than 15 miles at a time.

From what I've seen after replacing the lines and hose I'm content with drums. When I the truck the first thing I though of was putting disc on the front, then I realized the drums were not operating properly. Currently it would be one of the last things I'd consider doing. There is a long, long list of things this truck needs more, including rust repair.

[Hoosier Rick]

My 67 still has 4 wheel drums. I added a 3/4 ton booster to my 1/2 ton truck.(did not have power brakes originally) It will set the truck sideways on a hard stop at city speeds.
Highway speeds is where you aren't even in the same league with the 4 wheel disc, abs equipped vehicles you are sharing the road with.

[yuccales]

Originally Posted by CaptRMW

I have driven my share of miles with 4 wheel drums and I can tell you a panic stop at 70 miles per hour will likely make some skid marks but not on the asphalt.

No truer words have been spoken!

[toolboxchev]

Me I am different, Black Sheep different. I have 4 wheel drums on my rig. Properly maintained they stop on a dime when I want them too. I do not carry big loads anymore or do the rough driving I use too.

Story I got years ago was that Cadillac or Buick had patented them in the 1930's so they did not make it to the rest of automobiles until much later.

Do discs work better and are easier to maintain, absolutely! Do I wish to spent the extra money to do this on my rig, Nope, keeping it keeping on they way it was intended to be. 4 wheeled skids and all.

Whats in your ToolBox?

[jeffahart]

My disc drum with hydroboost is definitely an upgrade. I just called it an axle swap and a Hydroboost conversion... but it is a nice upgrade.


j

[jocko]

OEMs switched to them for a reason, many of them stated above. Managing your interval is as important with disk/drum or disk/disk setups as well - because most vehicles on the road today have ABS, which will outperform pretty much any disk/disk system that doesn’t have ABS - there’s no shorter stopping distance than the one that is right on the edge of a skid yet never skids.

[dmjlambert]

How do we get ABS for our 67-72 trucks?

[bill3rail]

Originally Posted by dmjlambert

How do we get ABS for our 67-72 trucks?

ABS would be another upgrade. Why? Because they are supposed to avoid wheel lockup. I believe wheel lockup reduces traction.

Bill