Greetings all,

I have a 70 F250 2/WD with PS/PB and 12X2.5" drum brakes all the way around.
I have completely re-done ALL of the brakes less than 12 months ago with NEW drums, wheel cylinders, shoes, springs, adjusters, and a master cylinder. I even replaced all of the rubber brake lines too.
I wanted to upgrade the front brakes to disk brakes but couldnt afford the extra cost at the time. Finding new front drums was expensive enough. Adding in the cost of replacing the king pins to accommodate disk brake spindles was more than I was prepared for. But thats not what I was posting about anyway.

After all of the work I have put into the exixting drum brakes the truck stops acceptionaly well for something that heavy with only drum brakes stopping it.
The problem Im having (Which is probably normal for drum brakes) is brake fade. It seems that stoppng the truck from normal speeds is fine, but quickly slowwing down from and then stopping from higher speeds of like 80-100 MPH the brakes just fade into nothing. Whats more is once it starts, it seems like the harder you brake, the less they stop.
I know the mechanics of a brake system so I understand why this happens. And I also know that I wouldnt have such a problem if I just didnt drive that damn fast. But my question is this.
Has anyone else expierienced this problem before and what can/did you do to minimise it.
I have already resigned myself to the fact that as soon as the king pins need to be replaced in my truck that I will at that time convert to disk. But being that Ive already spent bucks on brand new everything drum brakes. What should I do for now. Just slow down or what?

Sharkdance

 

that is one of the many reasons disk brakes were designed for . drum brakes dont vent heat very well and once heat builds you get brake fade. you might check with some of the different brake manufacturers as i heard recently one has new pads and shoes that are supposed to grip better with more heat. cant remember the name. other than that you are stuck with what ya got.

 

I thought the max. speed limit in Fla. was 70 MPH!

 

sharkdance, you might investigate having grooves put into your drums, a friend of mind had to go down 8 miles of hills to get to the bottom and by the time he was done his brakes on the drum rear were toast, he was replacing brakes every 3 to 4 days. so he had these grooves put into the drums and it allows air to get in there and cool em down. I don't know exactly who does the maching but check around.

 

Ok, I have bit my tounge several times over this thread - but, damn it, learn to drive with drum brakes. Ask any truck driver and he will tell you that if you are using your brakes to control your speed on a down grade you are just an accident waiting to happen. Downgrades are why you have gears in your transmission.

Same token, I see young people today race up to a stop sign and slam on their brakes - you should almost coast to a stop or you will be replacing shoes every 10k miles. Even with an automatic I do most of my slowing down with the engine doing the braking - with a stick I drop a gear.

The problem is that you guys are using trucks like cars, and driving like girls.

 

I'm a die hard with drum brakes. I have the parts to convert to disc brakes but still rely on the 2 1/2" x 12" drums on a 68 CS. Yes when empty they will fade with anything above 75 mph. 120 plus mph, just pray for discs. Motor is making more power today but the brakes are 1968 design. Disc is your answer to stop with todays high tech ABS vehicles.

Carl....=o&o>....

 

Heh, yea. Come to think of it, your right!
But that dont keep everyone from doing 80+

Sharkdance

 

Thanks for the advice, but I think I got driving with drums down. This is not the first vehicle with drum brakes that Ive ever owned and not the first time Ive experienced brake fade.
With a C6 trans and a manual valve body I know how to slow down using gears. And as Ive stated I know Im driving too fast to expect drum brakes to stop that much weight on a dime. But I guess you have never had anybody do an un-anounced brake check in front of you at 80+ MPH? Or come to the top of an overpass just a little too fast to find that all traffic has come to a stop 100 yards up the road?
Situations like this cause that queasy feeling you get when you have grabbed all the gears you can and are practicaly standing on the brake pedal just to feel them fade away. But, you must always have time to gracefully coast to a stop.

I dont think I drive my truck like a car. Even though Ive admitted to driving a little faster than I should. And driving like a girl might not be a bad thing, since Ive known some pretty damn good women drivers in my time.

Sharkdance

 

I stand corrected – I should have bit my tongue a few more times. You are likely an excellent driver – and yes, there are good lady drivers. They are skilled at talking on a cell phone while they apply their makeup and changing lanes in rush hour traffic.

Only one time did I pop over an overpass to find traffic stopped in front of me. I was driving a car with disk brakes – which worked well, as did the crumple zone, the core support, and my sideways engine and his rear end. They all helped me stop – I slid under a Chevy Nova with a hiked up rear end.

It was impressive to see his rear bumper sliding over my hood. That was the last small car I ever owned. I also quit charging so hard and racing in traffic. What surprised me the most is that it didn’t make a noticeable difference in the time it took me to get to work.

Anyway, I spoke out of turn and should not have said anything about your driving.

BTW – what size tires you running? Big tires add lots of strain on your brakes. With drums it is all about brake sweep area and the leverage the drum has on the tire.