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Drum brakes instead of disc brakes

What would it take to replace the rear drum brakes on a 2003 eclipse 4 cyl. with 165000 miles? Would it be worth it in the end?

Are you asking if you should replace the brake shoes on an existing rear drum brake system, or are you asking if you should replace the entire drum brake mechanism with a disc brake mechanism, or are you asking if you should replace an existing disc brake mechanism with a drum brake mechanism?

I am asking if I should replace the entire drum brake system with a disc brake system in the rear.

With discs ? No
Modern cars have other reasons going to discs on all 4 wheels that you might not realize the benefits from. One is traction/stability control.

You are not going to get enough of an increase in stopping power to warrant spending that much money on a 6 year old car with 165k on the odometer. Additionally, you would likely have to change other components, such as the proportioning valve. And, if the car has ABS, the ABS system may not work properly with a change in hardware.

Are you experiencing some kind of problem with your rear brakes that makes you want to upgrade them? Why are you considering this? What do you expect to gain?

There is no ABS to worry about. As to why, I’m looking to do as much upgrading and touching up since I am going to be keeping this car for the next four years of my college career. I guess I’m asking if it would be worth it to have disc brakes if I am keeping the car for that much longer.

Would not be worth the trouble, the rear brakes do a minority of the braking, drums are normally adequate for that. Just make sure they’re in good shape.

Drum brakes last just as long as disc brakes, so no, I don’t think it would be worth it.

The are only a few reasons I can think of to do what you are considering:

-if your current brake system is inadequate and unsafe.

-if you want to race the car on a track and need increased braking performance in those conditions.

-if you have millions of dollars laying around burning a hole in your pocket, you just bought some fancy rims that cost more than $1,000 each, and you don’t like the way the drum brakes look with the new fancy rims.

If you don’t fit into these categories, hold on to your money for something more important.

Don’t forget the parking brake system.

The front wheels provide 70% of stopping power. If you improve stopping power a significant 20% on the rear wheels, what is 120% of 30%? 36% for a grand total of 6% improvement in stopping power. You’d do much better with stickier tires.

And you never want your rear wheels to lock up anyway. There is little to be gained by doing this except the risk of failure of the retrofit and loss of rear brakes and their 30% of stopping power.

Yeah they look cool, but it’s just vanity. Since only 30% of the braking force is being provided by the rear wheel, they have to dissipate much less heat (43% of the front). Fade is not an issue.

The switch from drum to disk brakes is complicated, would involve a lot of modification, and would provide little to no benefit in braking performance. In racing a little improvement can be worth the money. For normal driving it isn’t worth the money. Drum brake shoes will last as long or longer that disk pads.

To upgrade the car, fix all the dents and touch up any paint that is showing age. Get the interior cleaned, including the carpet. Then put some money aside to pay for some repairs which a car with 165K will need over the next 4 years.

Don’t waste your money! Your car might perform worse afterwards!

Why? You are not likely to get better brakes. Brakes are part of a system. Making that kind of change is more likley to cause problems than to provide any benefits. You could end up with handling problems, than you are to improve the situation.

Are you experiencing some sort of problem???

No problems. I’m just looking to update the car to a more modern “spec”. Any other suggestions for that kind of work?

If you’re set on pampering this car:

  1. Make sure all the maintenance in the owner’s manual is up to date.
  2. Change brake and power steering fluids if they’re more than 3 years old.
  3. Change thermostat if more than 5 years old.

Go ahead, get your college degree, and you will probably forget about such a ------ project.

I believe that the reason that drum brakes are used on the rear of many vehicles with disks in front is that it is much easier to design a reliable parking brake system for drum brakes than disk. I expect that the most likely result of replacing rear drums with disks would be that you would spend a fair amount of money and end up with a car with no better braking when moving as well as a less reliable parking brake.

In addition to all of the other good answers, I think that the OP should focus on the reality that the car is now 6-7 years old, with over 160k on the odometer. Rather than spending money on “upgrading” a car that has already been driven for over half of its design life, the OP should concentrate on conserving his cash for the inevitable repairs that this car will need over the next few years. The transmissions of these cars tend to be a major trouble spot, and trans repairs will be very costly.

Personally, I think it has to do with more than that. I think it is a combination of vehicle weight, style, and performance.

When you look at motorcycles, the smaller lighter bikes usually have a single disk brake in the front and a drum brake in the rear, but once you get past 750 CC threshold, above 800 CCs, they start using a disk brake in the rear. When you get to the 1,000 CC mark, you start to see two disk brakes in the front instead of one, and when you get up past 1,300 CCs you see either dual disks in the rear or a beefier single disk brake in the rear.

The same goes for cars. Generally, the smaller, lighter cars can get away with drum brakes in the rear, but today’s larger non-commercial vehicles tend to have disk brakes in the rear. (Commercial trucks are a whole other story. They have drum brakes all around, but their entire brake systems are different.)

When you put fancy racing rims or chrome rims on your car, you don’t want to look at drum brakes. It is more aesthetically pleasing to see a shiny brake disk behind the fancy rims, which explains why economy cars with steel rims are more likely to have drum brakes in the rear.

For normal everyday driving, rear drum brakes work just fine for many vehicles. However, if you want to take your car on a race track, drum brakes would probably overheat faster. (This explains why the 250 CC Kawasaki Ninja has a disk brake in the rear. People actually race on these bikes unmodified.)

The OP’s reasons for considering this upgrade don’t fall into any of these categories, so I think it would be a waste of money.