Fixing my E-Brake for Inspection - do I really need to change ALL the brakes?
December 20, 2011 3:45 PM Subscribe
Fixing my E-Brake for Inspection - do I really need to change ALL the brakes?
In New York state and can't get my inspection because the e-brake (parking brake) won't hold the weight of my car.
My garage says that I need to replace rotors and brake pads along with parking brake shoes, hardware, and cables on both sides.
I'm not asking what's good for the car; I'm asking what's good to get this thing legally on the road. My [regular] brakes are working fine and we're recently checked out. Do I really need all this other stuff?
In New York state and can't get my inspection because the e-brake (parking brake) won't hold the weight of my car.
My garage says that I need to replace rotors and brake pads along with parking brake shoes, hardware, and cables on both sides.
I'm not asking what's good for the car; I'm asking what's good to get this thing legally on the road. My [regular] brakes are working fine and we're recently checked out. Do I really need all this other stuff?
You might, you might not. If the brakes are indeed fine, it's more likely a problem in the cable system for the parking brake. They tend to corrode, especially if you have an automatic transmission and only use the parking brake occasionally.
posted by tommasz at 4:37 PM on December 20, 2011
posted by tommasz at 4:37 PM on December 20, 2011
rotors and brake pads along with parking brake shoes, hardware, and cables on both sides.
Rotors and brake pads are terms for disc brakes. Shoes, hardware and cables are terms for drum brakes. Based on this, I'm going to fathom a guess that your car has front disc brakes and rear drum brakes. More than likely the e-brake engages the rear drum brakes, and when your rear brakes are bad the e-brake does little.
Replacing shoes will make your rear brakes work better and actually have a chance to keep the e-brake engaged. The rear brake hardware is almost always replaced as it tends to corrode. The cabling for the e-brake tends to corrode as well, so it probably needs replacement.
The question I would ask is why you need to have the front brakes done at the same time. It's possible the front brakes work with your e-brake, but it doesn't sound right given the drums on the car. I'd consider getting a second estimate.
posted by Mister Fabulous at 4:51 PM on December 20, 2011
Rotors and brake pads are terms for disc brakes. Shoes, hardware and cables are terms for drum brakes. Based on this, I'm going to fathom a guess that your car has front disc brakes and rear drum brakes. More than likely the e-brake engages the rear drum brakes, and when your rear brakes are bad the e-brake does little.
Replacing shoes will make your rear brakes work better and actually have a chance to keep the e-brake engaged. The rear brake hardware is almost always replaced as it tends to corrode. The cabling for the e-brake tends to corrode as well, so it probably needs replacement.
The question I would ask is why you need to have the front brakes done at the same time. It's possible the front brakes work with your e-brake, but it doesn't sound right given the drums on the car. I'd consider getting a second estimate.
posted by Mister Fabulous at 4:51 PM on December 20, 2011
Some cars have a really goofy hybrid parking brake system where the rear brakes are disks but inside the disk brake rotor is a second drum brake that is just for the parking brake. Only reason I can think of is some engineer has never seen disc brakes before and don't understand them, but anyway you can have both. And getting to the parking brake means you take off the disc brake stuff, and since you are already doing that you replace the pads at least, and the rotors if they are worn below spec (quite possible). Pads are really pretty cheap about 20-30 for most cars, rotors can vary widely from 30-40 to 200-300. The parking brake hardware is usually about 15 per wheel or so and shoes cost about what pads do. Time is about 2 hours for both I would say on most cars, maybe 1 on an easy car (which if your car has both sets on the rear wheels it aint an easy one).
If they are telling you for all 4 wheels it may or may not be necessary. Make them show you with measurements why they need replacement, it ain't hard and anyone who understands basic measurements (they will take a caliper to the discs/pads and show you how thick it is, say 0.5 inches and show you the service manual that says they need replacement once it is below 0.65 inches or some such-the measurements vary between cars). If they need replacement you replace them, it is your brakes after all. And you really don't want to harm yourself or even worse some innocent person who just happened to be at the bottom of the hill your worn out brakes couldn't stop you on. (not meaning to scare you-but you don't mess around with brakes).
posted by bartonlong at 5:13 PM on December 20, 2011
If they are telling you for all 4 wheels it may or may not be necessary. Make them show you with measurements why they need replacement, it ain't hard and anyone who understands basic measurements (they will take a caliper to the discs/pads and show you how thick it is, say 0.5 inches and show you the service manual that says they need replacement once it is below 0.65 inches or some such-the measurements vary between cars). If they need replacement you replace them, it is your brakes after all. And you really don't want to harm yourself or even worse some innocent person who just happened to be at the bottom of the hill your worn out brakes couldn't stop you on. (not meaning to scare you-but you don't mess around with brakes).
posted by bartonlong at 5:13 PM on December 20, 2011
The question I would ask is why you need to have the front brakes done at the same time.
Agreeing with Bartonlong, I am assuming hybrid - main braking on the disc with internal shoes for the handbrake.
posted by Brockles at 6:58 PM on December 20, 2011
Agreeing with Bartonlong, I am assuming hybrid - main braking on the disc with internal shoes for the handbrake.
posted by Brockles at 6:58 PM on December 20, 2011
Only reason I can think of is some engineer has never seen disc brakes before and don't understand them, but anyway you can have both.
Nope, the engineer understands how the brakes work. Disc brakes need active pressure to engage. Drum brakes have a self-energizing effect, when the wheel turns against the shoe, it naturally increases the braking force. You need a lot more force to energize a disc brake than a drum brake.
So for parking brakes -- which need to be on when the car is *not* running, you need to either hold a great deal of pressure, or you need a ratchet to pull a cable to move the shoes into contact with the drum. IOW, parking brakes on drums are vastly easier to implement, indeed, it's pretty much the only advantage they have. The same effect that makes parking brakes easier leads you to locking up the wheels under normal braking, makes brake fade easier to happen, and loads of other bad things.
Disc brakes need something like a cam or a screw to drive the brake pads against the rotor. This isn't hard in single pistol floating calipers, where you can just move the whole caliper, but multi-piston fixed calipers are very difficult to drive this way, and cars with that sort of rear brake tend to be the ones with a mini drum brake inside the rotor for the parking brake, or in a couple of cases on RWD/4WD cars, actually had an entirely separate brake on the rear drive shaft.
To get back to the original question -- the best way for us to tell you is for you to tell us the make, model and year is. Then we'll know what the brakes are, and can give you more than theoretical answers.
posted by eriko at 11:49 AM on December 21, 2011
Nope, the engineer understands how the brakes work. Disc brakes need active pressure to engage. Drum brakes have a self-energizing effect, when the wheel turns against the shoe, it naturally increases the braking force. You need a lot more force to energize a disc brake than a drum brake.
So for parking brakes -- which need to be on when the car is *not* running, you need to either hold a great deal of pressure, or you need a ratchet to pull a cable to move the shoes into contact with the drum. IOW, parking brakes on drums are vastly easier to implement, indeed, it's pretty much the only advantage they have. The same effect that makes parking brakes easier leads you to locking up the wheels under normal braking, makes brake fade easier to happen, and loads of other bad things.
Disc brakes need something like a cam or a screw to drive the brake pads against the rotor. This isn't hard in single pistol floating calipers, where you can just move the whole caliper, but multi-piston fixed calipers are very difficult to drive this way, and cars with that sort of rear brake tend to be the ones with a mini drum brake inside the rotor for the parking brake, or in a couple of cases on RWD/4WD cars, actually had an entirely separate brake on the rear drive shaft.
To get back to the original question -- the best way for us to tell you is for you to tell us the make, model and year is. Then we'll know what the brakes are, and can give you more than theoretical answers.
posted by eriko at 11:49 AM on December 21, 2011
Thanks, eriko. I have never dealt with multi-piston calipers and was not aware of that limitation. I am familiar with how Subaru implemented their front mounted parking brakes on discs from at least 1981 and was baffled why anyone would go to the bother of making two braking systems on some cars after learning how Subaru's system worked (Honda does something very similar on their 4 wheel disc brakes cars). I was also aware of the many, many limitations and defencies of drum brakes over disc and that further baffled me.
posted by bartonlong at 12:34 PM on December 21, 2011
posted by bartonlong at 12:34 PM on December 21, 2011
This thread is closed to new comments.
There is a financial element - if they are going in as far as to change (say) the parking brake shoes it may make sense to do the rest while they are there, but that's a different discussion to have. You'll likely have to remove all the other components to get to the shoes (depending on vehicle) and if they are ver 80% life it isn't that outrageous to recommend replacement as well, but it's recommend, whereas you suggest it is a need.
What exactly did they say?
posted by Brockles at 4:09 PM on December 20, 2011