Howdy y'all.

I made the mistake of telling a Chebby-luvin'
buddy of mine that I wanted to change my
'77 F-250 4WD's Dana 60 drums to discs by
using an aftermarket kit and rotors, and the
large Toronado/Eldorado calipers. This setup
will allow me to keep parking brakes, and make
brake service quick and easy. Ignoring all other
reasons I gave, he stated that I should forget
about towing anything heavier than a utility
trailer, and that for sheer stopping power, nothing
beats drum brakes, and that if I was smart I would
leave well enough alone, after all, "it's just a Ford".

My whole reason for the conversion is for ease of
maintenance. And while I will not scoff at the wisdom
of yesteryear, I will pursue my own preferences. I just
wish I knew something to say back to this clown. I've
had him on the end of a towchain, much to his shock
as I dragged him out of a stuck only to hear "I can't tell
anybody that an old Ford dragged me out". But I don't
mock him or diss his little K5 Blazer.

Any verbal ammo or smart comments back very welcome.
Please. Just once I'd like to cut him off at the pass witwise.

Thanks in advance

white_knight

 

The reason they use drum brakes is for lower initial cost and lower upkeep cost per mile. Otherwise, disc brakes win all around. A lot of < 26k gvw straight trucks come now with front disc brakes and you can even get some models with them on the rear too.

> and that for sheer stopping power,
> nothing beats drum brakes

If this was true, they would not be putting the more expensive disc brakes on 26,000 pound International trucks.

Ask him what kind of brakes, where SHEER stopping power is absolutely needed, are on jet airplanes

 

Many people will argue that rear disc brakes are just as hard to service as drums....especially with Ford's design. I changed them on a Mustang GT...sheesh, what a nightmare. The trucks aren't very easy either.

 

My F650 straight truck has the air brake setup which uses drums, with anti lock...I would love to have that kind of stopping power in my f250! However, I would even more like to have disc brakes all around the F250... After messing with everything about the rear drums, I would love the simplicity of putting the pads on and forgetting about them, instead of putting the drum shoes on, installing all of the springs and retainers, adjusting the shoes to the drum, and then trying to get the adjusters to work properly. Plus, checking brake wear on discs is much easier than pulling the drums off to check the shoes. And after crossing a creek, the discs are dry and ready to work quickly, while the drums take forever to regain stopping ability. And the disc brake setup weighs considerably less than the drum system. And Ford puts full discs on all of their newer pickups. And you can clean the dust out of a disc system without pulling a drum. And, well, if that doesn't do it, then you won't ever 'beat' this guy....

 

If drum brakes stop better than disk, why does NASCAR, CART, F1 and IRL all use disk? Have you ever seen drum brakes on a 747? Now that takes some stopping power!

 

The only thing drum brakes are good for it to keep you close to God...I should know, my '68 Scout has 4 wheel drums, and every stop has to be planned well in advance, and sudden stops require a little heavenly intervention!

(I'm in the process of adding front discs, but that's been a nightmare I won't visit here.)

 

If disc brakes stop better than drums, why to tractor-trailer trucks use drums??

 

Several recent heavy truck articles have addressed this. Safety agencies would rather have air disc brakes than drums on heavy vehicles. Air disc technology is available and very popular in Europe. The main reason that air discs are not used in the U.S. is cost. The production of air disc components remains low, keeping the costs high - when every trucking company in the country is cutting costs just to stay afloat, they are not going to pay the extra premium for the air discs.
As for the 747 issue - many heavy aircraft, including the Boeing 737s and 747s, the F-16, and Nasa's Orbiter all use DISC brakes.

 

i'll tell you what... we have drums on our fire apperatus, and with a fully loaded pumper i have had the brakes to the floor well in advance of the stop light, and all i can say is thank god for the Right turn of red law, and air horns... we usually have a brake retarder on that helps alot, because these brakes cannot take the abuse, but that day the road were a little wet and my Lt. told me to turn if off. never again. i talked to him afterwards and made my point clear... i can control wheel lock up, but not having no brakes.

We just ordered a new truck that has disc on it, and it is like night and day!

 

This whole "disc" brake on Heavy A/C stuff is a little misleading. The "disc" brake systems on those are NOTHING like they system on your car. In fact, they are closer to a posi differential than to your truck brakes. Just thought I'd throw that out there

 

I've owned two F150's that were nearly identical except for the brakes: a 97 reg cab stepside V8 and an 03 reg cab stepside V8. The 97 had front disc and rear drum, and the 03 has 4 wheel disc. The difference during standard and heavy braking is like night and day. Haven't had to panic stop yet in the 03, so I can't comment on that, but I can say that the 4 wheel disc wins hands down.

I would guess that the reason rear drums are (were) used in light trucks is that the bed is usually empty and before rear ABS was pefected (?) there would have been a lot of rear wheel lock-ups if the more powerful disc brakes were used in the rear.

 

> If disc brakes stop better than drums,
> why to tractor-trailer trucks use drums

Initial purchase price, cost of ownership over the life of the vehicle, training, an in place system, federal laws governing braking systems over 26000 gvw, etc. If it ends up costing $3000 extra over 300,000 miles (.01 a mile) and a guy has 100 trucks, it is not tough to see what the decision will be.

For a small owner that keeps his new truck for 700,000 (instead of leasing) miles there is no way he will go disc brakes if it costs an extra $0.01 a mile.

 

There was quite the discussion awhile back on the General board about the drum vs. disc controversy and big trucks. Basically what it boiled down to was $$$$$ as mentioned before. For one thing the replacement parts system is geared around drums for large trucks. If I remember correctly from that thread, there was a big push in the 80's to get big trucks rolling on disc brakes. It turned out to be a typical big lobby snow job win over the government in part due to the reason I gave above. It's a ridiculous argument but in this country, big money talks before public safety.

White-knight, it wasn't "wisdom" that led designers to put drum brakes on cars and trucks. It was ignorance.
By all means do your D60 disc swap. You won't regret it. When you're done, take that Chubby buddy of yours for a ride, slam on the brakes then ask him if he still thinks drums are better as he picks bits of windshield from his forehead.

 

I'm surprised nobody mentioned that the front brakes do most of the work. That is why you see way more front disks than rear.

I've got a 72 Nova with drums on all 4 corners. I've also driven many other autos with this configuration. It has been my experience that the drums are much more prone to "brake fade". They work great when cold but once they get hot you're done. True high performance driving is out of the question.

 

Drum brakes have a smaller hydraulic piston. It travels further than the piston on disc brake systems, but has less force. A lot of stopping power comes from the twisting motion on the system when the first shoe is applied. The rotating drum "pulls" the other shoe (which is somewhat applied) into the drum basically. Not all that effective.... Also, drum brake systems build up huge amounts of heat. Brake Fade-no-fun. Like everyone else said: It's cost that keeps 4-wheel disc off a lot of vehicles.....