Prolific CC Commenter Bryce posted this shot of his Hillman Minx titled “Drums out; discs in”. Well, that and a whole new front suspension and cross member, thanks to a more recent Hillman parts car he picked up a while back. So the question today is all about drum brakes: are they a dangerous nightmare to be avoided or are their limitations exaggerated?
Of course any car can benefit from disc brakes, but the issue about drums is not exactly black and white. A drum brake can be quite powerful, but the biggest issue is fade from /heavy/repeated use, as well as from being over-stressed. My first several cars were a Corvair and VW Beetles. With their rear engines, braking power was much better balanced between front and rear axles due to the rear engines. I never felt under-braked in them.
It’s also the reason why the original Toronado and Eldorado were so under-braked. With their front weight bias and lightly loaded rear axles, they simply overpowered their front drum brakes.
Size is of course a big factor too, in drum brakes, and some of the better American cars had quite massive front brakes, and finned too. I had a Peugeot 404 sedan and wagon at the same time. The sedan had discs; the wagon drums. But the drums on the wagon were huge and wide, and had double-leading shoes (meaning two wheel cylinders per brake). These were the best drum brakes I’ve ever used, and I liked them better than the discs in sedan, which also were unassisted. Ironically, I was tempted to swap out the sedan’s discs for the drums from a wagon.
The wagon’s brakes were also unassisted, but drums really don’t need assist, as they are self-energizing. The 404 wagon’s brakes had the most progressive and sensitive response of any brakes I’ve ever driven; the equivalent of a manual rack and pinion steering on a light car. A dream to use, and I’ve missed them ever since.
The drums on my ’66 F100 are modest, at best. They’re the same size as on a Ford passenger car, which is pretty pathetic. I made several trips up I-5 from Los Gatos to Eugene hauling our massive amount of stuff/junk, towing an un-braked (but pretty light) trailer). Getting out of the Bay Area during morning rush hour was more than a bit hairy, because if I left extra space in front of me, other driver constantly filled it in. I had one or two scary moments. But once out of the metro area, the roll up I-5 was fine, as long as I stayed on the right lane with the other big truckers. And I shifted down on the grades.
One time I had a transmission problem, and it kept popping out of second right on the longest and steepest grade of the trip, the Siskiyou Pass, and I only barely got the rig stopped, with all the pedal pressure I could summon! One stop, on cold brakes, and it almost didn’t fully stop at the end, the brakes useless.
Except for that hairy moment, which wouldn’t have happened if my transmission had stayed in gear, I’ve managed to get by ok with the drums on the Ford, even pulling very heavy loads, since I just keep my speed down and always am very cognizant of what gear I’m in on any grade. But Ford really could have put some larger brakes in these, like the ones used in the 3/4 ton F250.
So what are your experiences with drums? Live with them, or swap them out?
I grew up with a ’63 and ’69 VW beetle (drums all around) and learned to pump the bakes to keep them from fading down a hill or the exit ramp from the elevated highway.
All the remaining cars that I have owned had front disc and the 2005 Escape had disc front and rear.
Still to this day, I will pump the brakes as a reflex when exiting the highway or down an incline.
My first all drum braked car was a ’68 Mustang coupe. It had a 302 4bbl w/ manual steering and brakes. Very scary in rain or snow! I also drove a 75 Valiant for a time w/ four wheel drums. If you knew it had them, it stopped fine. Unfortunately a mechanic’s employee didn’t and wrecked it! If you kept the brakes dry and downshifted on hills both of my cars stopped no problem.
Senior Buicks like the Electra and Riviera of the late 60s had beautiful big finned aluminum drums up front and big cast iron finned drums in back. They were known to be good stoppers.Back in the day -you remember how in driver’s training class you were admonished to leave one car length distance for each multiple of ten miles per hour as a safe following distance.If you figure 15 ft. as a car length then at 60mph.that would be 90ft, as a safe following distance. Try to maintain that in modern commute traffic! That formula wasn’t just chosen to be arbitrary, it reflected the braking power of the cars of that period.
Cars from this era have to be operated within their performance limits, which are really very low. I grew up driving drum brake cars, usually unassisted. The power booster just made it easier to lock up the brakes until you learned how to modulate the pressure on the brake pedal properly. Do you remember going to the dealer and seeing a big red tag on the dash that read ‘Warning! Power brakes!” on the new cars? It’s actually easier to modulate the brakes without the booster but you’ve got to have a strong leg.
I’ve been daily driving my 70 mustang coupe with unassisted drums all round for about a year and five thousand miles.Since it has the optional 250 cid motor it came with five lug axles and 10in. by 2in. drums front and back. These are the same brakes that came with the base 302 V8. There are a couple of things that you can do to improve stopping power before changing to discs. First, rebuild the entire system. I found that I had two partially seized wheel cylinders, one in front and one in back. Surprisingly I was able to lock up the wheels anyway. Second, do not use organic brake linings. Use the semi-metallic linings. These have a higher co efficent of friction. and resistance to fade. Third, use better tires. You can usually find larger, wider steel wheels from a newer model that will fit and allow you to use a larger radial tire. The stock wheel on my car was a 14 in. 4i/2 or 5in. wide wheel with some whimpy 165 width tire. I’m running 15 x7in. Ford Ranger steel wheels with 215/60 touring rated tires. It all comes down to the tire at the roadway. After I got it together I took it out to a lightly used country highway with a 50 mph speed limit. Keeping an eye out for any approaching traffic I executed a few panic stops from 35, then 45, then 50 mph. I wanted to get an idea of how well it would stop and how it would behave in an emergency. It only pulled a little to one side and further adjustments improved on that. I felt a lot better knowing what to expect in that situation.
When driving in heavy traffic on the freeway I pay close attention to maintain a safe following distance and monitor traffic far ahead. My car will start losing speed as soon as I take my foot off the gas pedal. Much more than my fuel injected, overdrive transmission late model cars do. I don’t have to ride the brake to maintain my speed and following distance. If I was going to modify my car with greater power I would definitely want to add disc brakes up front. Right now I just take it easy and drive sensibly.
I would actually like to write up a full post on this subject and am getting my info together. I don’t know if that would be an appropriate subject to submit.
Sure; it’s a good subject. Send it to us via the Contact form when it’s ready.
My 66 Galaxie ‘vert (390, auto) stopped incredibly well and totally straight with its 4 drums…however, the power brakes were so intense it just took less than a toe’s worth of pressure. That, and the lack of a proportioning valve on the single-master brakes, made for a couple of memorable spinouts. The brake adjusters never worked right, though, and I always had to put a toe UNDER the brake pedal to pull it back up…it even left my auto shop teacher scratching his head.
My girlfriend had an 88 Tracer with the most pathetic drums in the back…they were so rusted that I couldn’t fix them. Ran on the front discs…
When one learns to drive, one *should* learn the art of engine braking (especially with standard-shift vehicles) in lieu of of in addition to pedal braking, which is of great assistance when anyone under the age of 60 hops into a 50+ year old car. In fact, when I drive my ’53 Ford F100, its short gears and flathead V8 do most of the braking. That works better in rural better than city driving, though!
No one learns on standard shift cars anymore because almost no standard shift cars are sold new in the US/Canada. Still, there are selectable gears on most automatics. “Select Shift” or “Sport Shift” automatics allow total control, once you learn to use them. CVT’s, however, seem to offer little manual override. I base this on recent rental car experiences.
I do a lot of mountain driving and even modern discs will overheat on trucks if lower gears are not used. The California Commercial Driver Handbook recommends not applying the brakes lightly all the way down a grade, but firmly applying them for a few seconds and letting off to allow them to cool. Great advice that has served me well, even in passenger cars.