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18 votes

Mechanic sent me this image and said my brake rotors should be replaced. Does this seem right?

The shiny rings on the rotors are the only parts that are doing any useful work braking the vehicle . The dull rings are rusty and are not serving any use. The rust rings will have worn the matching ...
HandyHowie's user avatar
  • 25.2k
9 votes

Mechanic sent me this image and said my brake rotors should be replaced. Does this seem right?

Those look to be worn and scored. As a minimum they need to be resurfaced, which many shops are not equipped to do. They may also be at or below the service limit so resurfacing is not an option. If ...
jwh20's user avatar
  • 12.1k
8 votes
Accepted

Stopping power diminishing despite good-looking brake pads?

If you did the work yourself, did you have the rotors turned or use new rotors? And if you did, did you bed the brake pads to the rotors? Both of these things are rather important when changing brake ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes

Do extremely rusty disc brake rotors/pads need to be replaced?

Repair shop liability issues dictates SAFETY FIRST. Brake repairs are safety issues so there's no cheap economical repair. However, you can, if possible, seek out another repair shop and ask for an ...
F Dryer's user avatar
  • 976
6 votes
Accepted

How does the brake fluid return to reservoir in Disc Brakes after brake pedal is released?

In the caliper, the seal is designed so when you press the brake pedal and fluid enters, the seal twists sideways. When you release the brake pedal, the force of the seal pushes the piston and thus ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
5 votes
Accepted

Does engine braking help stop a car faster in an emergency?

No, it does not, at least not in a car that has a properly working braking system. In every modern car the brakes are capable of locking up the tires on both the front and rear axles. Today that ...
jwh20's user avatar
  • 12.1k
5 votes

Mechanic sent me this image and said my brake rotors should be replaced. Does this seem right?

The image doesn't say much more than "the braking capacity of this wheel is not at 100%." What you need to address is: What is causing this wear pattern? The image suggests there is a ...
Dug's user avatar
  • 81
5 votes

What can cause two deep "stepped" grooves in a rotor?

It looks as though to me you've worn down through the friction material and into the rivets which hold the friction material to the pad. There are a lot of pads which don't use rivets for this and ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
5 votes

Spongy brakes in a 2004 Toyota corolla

Treat this as a new problem, and forget all the repairs that have been made. The first step is to eliminate the possibility that there is a brake fluid leak. Carefully and accurately mark the brake ...
MTA's user avatar
  • 5,935
4 votes

Do extremely rusty disc brake rotors/pads need to be replaced?

Rust on rotors obviously is normal, and normal braking will clean this surface rust off in a short time. But after two years of sitting, it's very possible or probable that the rust has penetrated too ...
Jupiter's user avatar
  • 3,187
4 votes
Accepted

What can cause two deep "stepped" grooves in a rotor?

The 2 “step-like” grooves that you describe are all that is remaining of the operational part of the brake rotors. The rest of the surface is covered in rust and is not being used at all for braking. ...
HandyHowie's user avatar
  • 25.2k
3 votes
Accepted

Is it normal for rust to appear on brake disks within a couple of days of buying a new car?

Many cars do that in very short order. It's just light surface rust that gets rubbed off the first time you brake. Bare metal, often hot, plus water and even salt makes for quickly forming rust. ...
jwh20's user avatar
  • 12.1k
3 votes

Mechanic sent me this image and said my brake rotors should be replaced. Does this seem right?

I am unsure about the rotors, but a brake overhaul is definitely needed. Most of the time the mechanics decide that a job isn't complete, unless everything got replaced: either because they want more ...
Martin's user avatar
  • 8,448
3 votes
Accepted

Sudden complete brake failure

If there were a simple and obvious answer to this riddle, such as low brake fluid or a gross brake fluid leak, one can assume that any mechanic who has been in business more than 15 minutes would have ...
MTA's user avatar
  • 5,935
3 votes

Accidentally scratched the inner cylinder of brake caliper during rebuild - should I worry?

Leaks should be your #1 worry with brakes. Leaks means loss of fluid, which could lead to loss of brakes. That is terribly worrisome to me. Secondly, the problem with the scratch is, if the piston ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
2 votes

Brake noise only when releasing brakes

It could be your brake booster. The brake booster is the device that puts the "power" in power brakes. It operates from engine vacuum. A momentary sigh from the brake booster is harmless. To ...
MTA's user avatar
  • 5,935
2 votes

2002 gmc sierra 2wd rpms rise when applying brakes

I think you have two different issues here. The first one sounds like you have a vacuum leak in your brake servo/booster. When you press the brake, the booster uses vacuum provided by the air intake ...
HandyHowie's user avatar
  • 25.2k
2 votes

What can cause two deep "stepped" grooves in a rotor?

That is an unusual wear pattern. I think it is either a damaged pad or a bad caliper. Either way: It is time for a full brake job. Inspect the guide pins for unusual wear. Clean the caliper slides. ...
Martin's user avatar
  • 8,448
2 votes
Accepted

Squeaking sound from the wheels after taking out of storage

There's a few likely culprits: If the sound is coming from one of the back wheels it could be that the parking brake is not releasing properly. Most cars have a separate braking system for the ...
GdD's user avatar
  • 16.4k
2 votes
Accepted

Why doesn't applying the brake auto-apply the clutch in a manual transmission car?

I think the main reason why is, every time you even touch the brakes you'd be slipping the clutch. This would destroy a clutch in short order from overheating, especially in stop/go traffic. If you ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
2 votes

I only did a brake fluid flush on one side before I had to stop and run an errand. Do I need to start over?

There's no need to redo that side, as long as the fluid reservoir was filled with fresh fluid you are good to go, just do the other side as normal. There may be a very small amount of fluid from the ...
GdD's user avatar
  • 16.4k
2 votes

Do extremely rusty disc brake rotors/pads need to be replaced?

Even two years of rust will not have degraded the rotors in any significant way. You might get a bit of pitting but that will actually help braking performance - just like more expensive dimpled discs....
RJM's user avatar
  • 21
1 vote

Do extremely rusty disc brake rotors/pads need to be replaced?

It depends whether there will be vibrations when you remove the rust or not. If so, you should remove at least the rotors. The best way would be to machine the rust off - in that case you may get an ...
Juandev's user avatar
  • 151
1 vote

Help Needed! My vehicle (2015 Nissan Sentra) is not starting after Brake Job. - DIY

It sounds like you have run down your battery. You hear a click but there's no crank and the dash lights go out when you try and start, that's a classic low voltage situation. Either your battery is ...
GdD's user avatar
  • 16.4k
1 vote

2000 Chevy Silverado abs engaging 5mph

The following can also cause issues like this - Cracked Reluctor Ring Rusty Reluctor Ring Worn wheel bearing (allows the ABS sensor to move away from the reluctor ring) Rust stopping the ABS sensor ...
HandyHowie's user avatar
  • 25.2k
1 vote
Accepted

Brakes seems to work on front wheels only

From your description, there is nothing wrong here. As your mechanic stated, the front brakes get hotter than the back brakes. This is because the front brakes do about 70% of the braking for the ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
1 vote

Why doesn't applying the brake auto-apply the clutch in a manual transmission car?

When driving down a long steep hill, it's sometimes advantageous to downshift and use engine braking instead of your service brakes, which can overheat if applied too long. With a device such as you ...
MTA's user avatar
  • 5,935
1 vote
Accepted

Self Applying Brake Pedal after Rebuilding Hydroboost - 2003 Hummer H2

So it looks like the issue was that I did not attach the bracket arm (I don't know what you call it) that is on the input rod & piston assembly to the end of the head of the spool assembly. See ...
Wolf Zwiener's user avatar
1 vote

What can cause two deep "stepped" grooves in a rotor?

It looks like you have a millimeter or two of pad material remaining; see picture below. You really should have unbolted the caliper and removed pads from the bad side and good side of your car for ...
MonkeyZeus's user avatar
  • 1,187
1 vote

Does engine braking help stop a car faster in an emergency?

In fact the opposite - it will take longer to stop with the clutch engaged. On a manual drive [stick shift] you would get some slight engine braking in 4th gear at maybe 40mph+, but if you were coming ...
Tetsujin's user avatar
  • 217

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