Preparing a car for races or a track day requires more than just adding more power and lowering your car. Upgrading your brakes should also be one of the first things to think about, especially since more power requires more braking power.
Using better brake fluid and improved pads is a great way to improve the performance of your braking system, but your calipers might become a bottleneck. Sometimes when you really put pressure on your brakes, you’ll notice the pads are wearing diagonally. This is often caused by worn caliper bushings. One of the best solutions for this issue is a brass caliper bushing upgrade. We’ll go over the pros, cons, and the process of upgrading your brakes with a brass caliper bushing on a BMW E36, although the information below applies to most makes and models.
What Are Brass Caliper Bushings?
Each set of caliper activated brakes has caliper bushings. They’re used to bolt the down the calipers, but also eliminate any sort of play or vibration transfer. More importantly, caliper bushings play a major role in applying even pressure to the pads, which allows the car to brake evenly and effectively.
Most stock cars have rubber caliper bushings that wear over time. Replacing them isn’t a complicated process, but if you notice your pads wearing unevenly, you might want to think about upgrading to brass caliper bushings even if you’re using the car as a daily driver.
If you own a older gen BMW, there’s a chance that your car features floating brake calipers, as opposed to fixed ones found in many cars. As the caliper’s piston pushes the inner pad toward the rotor, the entire caliper can slide or “float” to equalize that pressure with the outer pad – ensuring that the rotor stays centered between the two pads.
The caliper slides on guide pins that are supported by rubber bushings. The problem is that these bushings allow flex into the system, particularly if the bushings are old or worn. This means the communication between your foot and the brakes themselves isn’t as direct as it could be. In addition, bushing flex (among other things) can allow brake pads to wear unevenly if this flex means the pad doesn’t mate squarely with the rotor.
Pros and Cons of Brass Caliper Bushings
Like any other car upgrade, brass caliper bushings have their pros. This upgrade is not without compromise. Namely, in exchange for the benefits described in above, you will need to add caliper guide bushings to your list of things on the car requiring routine maintenance.
But let’s be honest, if you’re reading a DIY such a thing is hardly intimidating to you. In the next part of the article, we’ll go through the reasons why you should and why you shouldn’t upgrade to brass caliper bushings. If you’re running M3 brakes on your E36, you should also consider doing this upgrade.
Compared to regular rubber caliper bushings, there are a couple of distinctive reasons why it’s better to upgrade to brass caliper bushings instead of just replacing the bushings with another rubber set.
The first reason why upgrading to brass caliper bushings kit is a good idea is that the brake pads will wear evenly. Brand new rubber bushings will accomplish the same thing, but for only so long before they begin to deteriorate. When the pad twist is eliminated by adding brass caliper bushings, the pads will last much longer than regular bushings.
Lastly, with an initial investment of just around $50, it’s more affordable to do the upgrade than to leave the factory rubber bushings.
The downside of upgrading to a brass caliper bushings kit like this we’ve used on our BMW E36, is that no significant improvement can be felt if you do the upgrade on your daily driver. Yes, the brake pedal should feel better, but you’ll get few tangible benefits on the streets. This upgrade is most beneficial for racing and track cars.
Upgrading to brass caliper bushings won’t damage your car, but it will require a bit more maintenance compared to rubber caliper bushings. These need to be cleaned and greased regularly in order to function effectively.
How to Perform the Brass Caliper Bushing Upgrade
If you decide to upgrade to a brass caliper bushing, here’s a step-by-step guide on how to do it on a BMW E36. The process is similar to most BMW models, with slight differences.
Step 1 — Remove The Wheels
The first step is removing the wheels. You should start loosening the bolts while the car is still on the ground after which you’ll need to place your car on jack stands, making sure everything is secure. You can also put the wheels under the car just in case.
Once the wheels are removed, you’ll have access to the brakes.
Step 2 — Remove The Caliper Spring
Next, remove the caliper spring. They’re usually easy to remove, but be cautious because these springs are preloaded and can easily smack you in the face causing an injury. Once removed, check each spring visually for wear and damage and replace if needed.
Step 3 — Remove The Calipers
With the springs removed, remove the calipers. This is done by unbolting guide pins located on the backside of the calipers using a 7 mm Allen key. When the bolts are undone, it’s a simple process to remove the calipers.
Step 4 — Remove The Existing Brake Caliper Bushings
The next step includes removing the rubber caliper bushings. When you remove the brake calipers, make sure that they’re supported by a ziptie or a piece of wire, so they don’t hang on the brake lines. Using a flathead screwdriver, wedge out the rubber bushings. If the bushings are already worn, there’s a good chance they’ll break while trying to remove them.
This part of the process might take some time especially since you’ll have to make sure you’ve removed all the rubber from the bushing housing on the caliper. These rubber bushings are known to stick due to heat and age, so preparing the housing for the brass caliper bushing is of the utmost importance.
Step 5 — Check The Fitment Of The Brass Caliper Bushing
Once the rubber bushing are completely removed, check if the new brass caliper bushing slides into place easily. If it’s catching on something, you can try to sanding the bushing hole using sand drum fitted to a dremel tool, or an equvialent. More often than not there’s corrosion in there which could prevent you from inserting the brass bushing.
Step 6 — Fit The Bushing To The Caliper
Before fitting the new brass caliper bushing, make sure to grease it with high-temperature grease. Once done, you can place the bushing inside the caliper and secure it with circlips. Make sure you place the flange closer to the rotor while the circlip should face away from the rotor.
Step 7 — Fit Guide Pins To The Bushings
The last step includes greasing the guide pins with high-temperature grease as well before placing them inside the bushing. This will ensure the new upgrade will work efficiently and without any issues. Note that the guide pins should be torqued to 22 lb-ft. Any more torque can make the caliper bind on the guide pins.
After you’ve upgraded the brass caliper bushing, you should fit everything back in place and the job is done!
Find Brass Caliper Bushing Upgrade Parts!
If the brass caliper bushing upgrade is something you feel can benefit your rig, you’ll need a few parts to make it all work.
All you have to do is visit eEuroparts.com, select the make and model of your car, and you’ll get a list of all the parts you need to perform the brass caliper bushing upgrade on your car. By using our product navigation tool, you’re guaranteed a good fit!