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Maintenance of drum brakes

How does one maintain the drum brakes? For Disc brakes, one changes the rotor and the pads regularly. The drum brakes have shoes. How often do they need a replacement? Is there anything else that needs servicing?

I do not remember servicing drum brakes as long as the car is in my possession, i.e. 9 years. I bought it pre-owned, 3 years old with 75K miles. I never got any service records.

Many thanks in advance.

Brakes is brakes. The friction material wears out. On a disk brake, the caliber squeezes the pad against a rotating disk. With drum brakes the wheel cylinder forces the shoe against a rotating drum. The shoe has friction material that eventually wears out just as the friction material on the brake pads wears out on disk brake vehicles. There ain’t no such things as maintenance free brakes.

How often the brake shoes need to be replaced is a function of…
How you drive…
Where you drive…
AND…
The make and model of your mystery vehicle.

For instance, GM’s disastrous H-body vehicles (Pontiac Sunbird, Buick Skyhawk, Chevy Monza, Olds Starfire) typically needed to have their brake shoes replaced every 12k-16k miles. However, well-designed vehicles were rarely in need of brake relining as often as those GM pieces of junk. What type of vehicle are you driving?

And, no matter whether one’s car has disc brakes or drum brakes, your brake fluid should have been flushed/replaced at least twice already. Unless you know that the brake fluid was flushed/replaced w/in the past 3 years, you need to do it.

I put new shoes and drums on my 1999 Honda for the first time a couple years ago. The only earlier new parts were new wheel cylinders. I usually remove the drums and spray the innards with brake cleaner each fall when I put on my winter tires. That is probably more attention than they actually need. I have bled the brakes, pumping in new brake fluid, front and rear, a few times.

If you are curious you could remove the drums and inspect things, but they probably don’t need any maintenance or repairs until something goes wrong. The front disc brakes do the lion’s share of the braking work and need more frequent service.

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You didn’t say what kind of vehicle we’re talking about here, but often you see drums on the rear and discs on the front. If that’s the case with your car, it’s not surprising that they last a long time, because the rear brakes don’t work nearly as hard as the front brakes and therefore can last much longer before they need replacement.

When servicing drums, check the wheel cylinder for leaks and replace if warranted. Check all the other hardware in there as well, and replace anything that’s gone bad.

Personally I find drums thoroughly unpleasant to work on. Hopefully you don’t feel the same way after your first round. :wink:

First round is always unpleasant. But a brakes specialist prefers them.

Most drum brakes now are only in the rear (on cars), and the rear brakes tend to wear less often than the front brakes. They still need replacing from time to time and the drum also can need replacing, same as disc brakes. The last ones I did though was on my 86 Park Ave. and broke my tool and never expect to do drum brakes again.

Just did front (disc) and rear (drum) on my 2005 gmc 1/2 ton truck for what appears to be the first time at around 145k miles. They weren’t completely worn out on the front or the rear, but I went ahead and replaced both. If the new pads and shoes last as long as the originals, I doubt I have to do it again. Drum brakes aren’t too bad to replace after you’ve done it a few times. More parts than disc brakes, of course. But I find it kinda enjoyable on a Saturday afternoon.

I would also recommend that if you’re going to service the drum brakes yourself, get the basic drum brake service tools.

One tool removes/installs retaining springs, one removes/installs return springs, and one turns the star wheel to back the shoes off the drums so that the drums can be removed.

These three inexpensive tools makes doing a drum brake job much faster and easier.

Tester

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I’ve had good luck with the spring installation tool that came with my kids trampoline and a big flathead lol. But those you show are definitely nicer.

Drum brakes on the 05 Sierra have one large horseshoe shaped spring and one small spring up top. That kind of threw me for a loop on the first side.

What if the vehicle in question is a dually with a full floater rear axle . . . ?!

I wouldn’t say it’s “bad” . . . but that scenario I just named is a LOT of work, especially if you have to actually replace and/or machine the drum(s)

If you replace/machine drums, replace wheel cylinders, shoes, axle seals, hub seals, hardware, and adjust the parking brakes . . . you won’t be saying it was “kinda enjoyable”

Well ya got me there. That sounds like work. Even doing all that extra work on a regular half ton truck (replacing wheel cylinders and axle seals) would probably exceed my “enjoyable Saturday afternoon” limit.

On econobox’s with front disc and rear drums, the rear shoes rarely need to be replaced, at least in comparison to the front pads. For example I just recently replaced the rear shoes on my 27 year old Corolla for the first time, w/well over 200 k miles on the clock. This all depends on the make/model/year and driving style of course. In my case I was hearing a little scraping noise from the rear when braking. I pulled the driver’s side rear drum and there was still plenty of material on the shoes. So I figured it was just rust making the noise. But the scraping noise was starting to get louder over the next few months so I pulled the drum on the other side. Sure enough the shoes on that side had reached their wear limit.

If you want to service drums – definitely a diy’er friendly task – you need some special (but relatively inexpensive) tools as posted above. Don’t try it without those tools on hand. There are some tricks for removing the drum, so if you get to that point, post here for some tips. The most important part of servicing drums is to only work on one side at a time, so you have the other side as a reference how the parts fit together. If you get the parts from both sides mixed up there’s a lot of permutations to go through which will waste your time figuring the correct configuration again. I always draw a sketch of how the parts fit together before taking the first side off as a backup. Taking a cell-phone photo makes sense too.

Understanding how the forces are used in that configuration to stop the car is helpful too, especially if you at a scientific type. There’s a thread of mine here where that topic is discussed, I’ll check to see if I can find it.

ok, found it

In addition to the tools shown above, you will need a thin but not too short flathead screwdriver. I have the brake spring removal and installation pliers and the adjusting spoon but not the retaining spring tool. I find that needle nose vise grips work just as well if not better and they are handy for putting the emergency brake lever retaining clip back on. The thin screwdriver is to lift the star wheel lock so you can back off the adjustment to get the drum off.

Doing one wheel at a time is good advice, just remember the left and right rear wheels are mirror images of each other because the parts match up not by left or right by looking at them but by being toward the front or rear of the car.

I used to like working on the rear brakes of the 50s and earlier Chrysler products. There were no emergency brake parts to work on.

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Wasn’t the e-brake on the drive shaft on 50s Mopars?

Thank you, everyone.

Its an econobox, 2006 Sentra, front disc brakes, the rear ones are drums. The current odometer is 108xxx.
Brake fluid changed 2 years ago and the mechanic’s comment, there was no need of it. The fluid was in pretty good shape!!

@VDCdriver
Driving is mainly in the city, light to light traffic (so a lot of braking), rarely goes beyond 40mph. I do not race AT ALL, rarely in the rush to run from the light to light. I know the limits of the vehicle. My wife’s comment, there are people behind you, don’t drive like a granny’. I think that should give you an idea.

@shanonia
I am DIYer, do my fluid changes and little here and there work, but I try to avoid working with the wheels and brakes. I don’t even rotate the tires myself because I always think I could end up messing something up. I am STILL not very clear on how to use a torque wrench, so I just stay away from this.

I have seen some YouTube videos and I think I will be able to do it but I will stay away from it.

The primary goal of this post was if there is/are any ‘standards’ for replacing either of those, like rotors, brake pads, and brake shoes, like thickness etc.
Last time, when I took Forester for inspection, the mechanic replaced rotor as well the brake pads. I thought it needs to be replaced in a pair (like the rotors and the pads) but then I learned it is not so.

Hence, I am trying to figure out when should I change these (rotor, pads, shoes etc)?

Thanks again.

Listen to your wife and at least don’t be a rolling road block .

Change shoes and pads when they are 80 % worn out .

Thanks.
How does one calculate 80% in rotor thickness?
Is there is minimum thickness for the pads?

Pardon me if that sounds silly question. I am assuming , rotors, pads and shoes have a standard thickness for a certain class of vehicles. So there must be a minimum thickness, like the tires?

I am never a rolling road block. I drive 3-4 miles above the speed limit. If somebody wants to do 40+ in 30, they can do it, I will not. And if that makes me a rolling road block, so be it. Our neighborhood is surrounded by Benz and beemers. They think they are driving on a highway (on a city road).
Not a single ticket in 19 years of driving, touch wood. My wife, 2 crashes, no bodily injury, luckily.

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Rotors have a minimum thickness specification. It is usually stamped on the rotors. Pads should be replaced when approximately 80% thinner than new pads. One way to determine when to change pads is if the pad is as thick as the backing plate that it is attached to or thinner, it is time to replace.

I use 1/8" as a minimum on the thinnest pad, other pads will have more.