The Stovebolt Site Forums The Shop Area Driveline Power Drum Brakes

I was sitting here about to write a check for a Disc brake kit when I started to wonder if I was about to spend too much for good safe brakes. I know you can't cut corners when it comes to brakes, but I wonder how power drums compare to power discs.

I've read that drum brakes stop better than disc brakes. The only 'con' is they can fade with heavy use. So why go to discs?

I would like to hear from anyone who has done a dual master/power brake set up on an AD truck. Do you like it? Was it worth the time/money?

I haven't added disc brakes, and the reasons are two: I don't drive fast enough to need them. I enjoy feeling safe and at any speed over 60 with stock suspension, steering, etc (including the roads we have here) I don't always get that feeling. And two...drum brakes have always stopped my truck just fine.

Before the 1952 Chevy 1/2 ton, I had a 1951 GMC with the smaller 6 and drum brakes always worked fine in that one also. As for dual master cylinder, I haven't done that either. I can see the benefit, naturally but it seems to me as long as you have a good master cylinder kept in good repair, good brake fluid changed regularly, sound brake lines and good wheel cylinders kept in good repair and sound anchor nuts, the system should be fine. Actually, it stops better than many cars I've owned and with reasonable enough pressure that my wife can drive it well. I haven't seen the need to spend the money to change. Good luck no matter which way you go.

That's why vehicles with single m/c had EMERGENCY brakes. Now days with dual m/c's we have "parking brakes". Go figure!

Alvin,

All my single master cylinder 1/2 ton trucks have parking brakes.

My 2-ton COE has a single master cylinder propeller-shaft [i]parking brake[/i].

I hear you Tim, I like to pitch a rock in the wood pile once in a while.

I just find it interesting that on todays models most of the parking brakes are of the nature you push them down with your foot and then push with your foot to let them off.
In a "dire" situation it would be hard for even the most experience driver to use the parking brake as a way to stop a vehicle....unless of course you just lock it down!
I taught all my kids how to use a "park brake" to stop a car by manipulating the foot or hand brake to get a car stopped and they could do it very well, especially the ones with the "park brake" between the seats with the little release button. It was harder to hold the foot release lever out and use the foot brake but they could/can do it.

....but I hear you loud and clear!

I only posted the comments because I do not know how to use them in an emergency.

Yes I do, if the hydraulic system fails, you then have an emergency and can and should try the parking brake.

I didn't want a new person to be looking in a Shop/Owner/Operator Manual for them by the wrong name. I know - I'm a jerk - sorry.

Your to kind to yourself Tim. But we all still love ya

When you moving pal. I still have the hot dogs and Pepsi waiting.

......and I understand how important it is for "newbies" to be taught correct principals which may save their life. Thanks to you for pointing that out.

So, do you mind if I re-highjack my thread? My emergency brakes are rebuilt and work great. My question was regarding power drum brakes.

I plan to replace the single resevoir with a dual resevoir master cylinder. When most people upgrade their brakes they like to go with disk brakes. I'm simply wanting opinions from those who've gone to power drum brakes. Was it worth it?

I put power drum brakes on a customer's 1958 PU.

On a car where you can rest your foot on the floor while putting on the brakes you have better control of the pedal pressure.
On these old trucks where your foot is no where close to the floor you do not have the same control. The forwards inertia tends to make you put the brakes on harder than you want.
That was my and the owners complaint. He ended up selling the truck in part because of this problem.

The owner had me put a power booster on this truck before having me look at the brakes. As it turned out the drums were all .100" or more over causing limited shoe contact. If he would have put new drums on first he would have not needed the power assist in the first place. As I said above, it stopped too good after I installed new drums.

twotone, to stay on topic,I should have added that I have a dual master cylinder and power drum brakes on my 52panel. They work fine and have for the past 3 years. No problems. Stops fast and straight.

BTW: Drum is not better than disc in any way. Front especially.

Except in deep water conditions.

Pre '68 Dave, that's a great point; more power needs more control and the way the brake pedals work on these trucks, you don't have the fine control you might want with power brakes.

Achipmonk, do you find you have a problem with controlled brakeing as suggested by Dave?

The only real problem I have with the original brakes is at the begining of a hard, or panic brake, the truck wants to pull to the driver side momentarilly. This is due, I believe, to the fact that one brake line from the master runs to the front driver side brake while all four remaining brakes work off of another shared line. This seems to get worse when the brakes get wet.

The real reason I want to upgrade my brakes is for safety's sake. I like the way they work, but I do find myself caught up in trafic in Des Moines and other places where the brakes get a work out, and a sudden loss of brakes would be dire.

If you ask fifty people what to do about brakes, twenty five will say 'well maintained stock brakes are all you need' and the other twenty five will say 'you got to have a power dual res master with discs to be safe'.

Well, I am going to install a dual resevoir master cylinder but I want to know if power brakes is really worth it? Are disc brakes really worth it? Can I go 'middle of the road' with power drums or is that kind of pointless?

Here's something to consider; Disk brakes are not self energizing, and in anon-boosted system, can take excessive pedal pressure to get them to effectively stop a vehicle. The Bendix style drum brakes, properly called Duo-Servo, are self energizing. This self energizing action will allow a non assisted drum system be more effective than a non assisted disk brake system. With an assisted system, drums can get very touchy, particularly if they're not properly adjusted. Disk brakes are much more predictable in an assisted application.
I can see disk brakes if you plan on oversized wheels/tires, or possibly if you do lots of driving on twisty or mountain roads. But for normal driving, non assist drums work just fine, even running highway speeds.

Quote- "Achipmonk, do you find you have a problem with controlled brakeing as suggested by Dave?"

...twotone, you can ask my wife that question. She's been with me two or three times where I had to stand on the brakes and the panel went straight and braked hard. No problem.

I'm trying to remember what I just read on page one....It sounds like you may need to check the routing of the lines to the front brakes. I can't remember TWO separate lines from the M/C going to the front brakes. (I may be entirely wrong but....)