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Brakes

BOSCH PREMIUM BRAKE PADS

Though many automotive service intervals have been lengthened or eliminated altogether on late model cars and trucks, brake pads are still a high wear item that require periodic replacement. The linings wear every time the brakes are applied, so after thousands of stops the pads eventually wear down and have to be replaced. Stop-and-go city driving is especially hard on the linings, but so too is driving in hilly or mountainous terrain. Hauling extra cargo in a vehicle or towing a trailer also increases the load on the brakes and accelerates wear. So by the time most vehicles have 45,000 to 70,000 miles on the odometer, they need new linings.

When the pads are replaced, most vehicle owners today want the best replacement linings that are available for their car or truck. They want stopping power that's as good as or better than the original equipment linings. They want quiet brakes that won't squeal, rattle or groan every time they step on the pedal. And they want linings that are going to last. So why not give them the best? Give them Bosch.

The new Bosch Premium Brake Pad line provides domestic coverage for:

• 97% of late model minivans
• 95% of full-size pickup trucks
• 89% of sport utility vehicles (SUVs)
• 87% of late model cars; and all with only 62 SKUs!

The target market for the new Bosch Premium Brake Pad line includes the most popular late model cars, light trucks, and minivans on the road today because these vehicles represent the most plentiful and profitable repair opportunity. People who drive newer vehicles are more likely to spend more on repairs to maintain their vehicles than drivers of older vehicles. It's a dollars and sense decision. That's why premium replacement linings are usually the best choice for this type of customer.

WHY BOSCH IS THE BEST
The first thing you'll notice about the new Bosch Premium Brake Pads is that they don't look like other aftermarket replacement pads. Bosch uses only the highest quality stainless steel for the pad shims. This provides the ultimate in corrosion resistance, durability and reliability, which translates into longer noise-free performance. This OE look and quality is everything you'd expect from Bosch.

The pads also have a patented graphite enhanced powder coating to protect the steel backing plate from corrosion. The coating provides protection in even the harshest environments, and can withstand temperatures up to 1100°F. The powder coating is impregnated with graphite and helps the pad slide on the caliper housing. This reduces noise and caliper piston face wear for longer caliper life.

Pads are also slotted and chamfered for quiet operation - a feature you'll only find on premium quality linings. Chamfered edges allow the pads to engage the rotor more smoothly, which reduces chatter, vibration and noise. Slots also help dampen noise and allow a path for hot gases to escape under severe braking conditions.

The beauty of Bosch pads is much more than skin deep. Vehicle specific formulated semi-metallic friction materials are used that provide exceptional stopping power and long life. Extensive testing assures that the friction compound is the best possible choice for each and every application. Bosch follows strict QS9000 and ISO9001certification procedures to maintain product consistency during the manufacturing process and to make sure each and every set of pads meets Bosch's stringent quality standards.

PREMIUM STOPPING POWER
Tests have shown that Bosch pads outperform most competitors by a significant margin. Bosch pads equal or better the stopping distance of the OEM pads on most applications. How do Bosch pads achieve such outstanding performance?

Bosch Premium Brake Pads incorporate distinctive multi-layer technology. Specifically formulated carbon/semi-metallic friction compounds, including special platinum-enhanced materials, provide exceptional stopping power with reduced noise over a longer performance life. Beneath these materials, an exclusive underlayer, isolates noise and reinforces the bond between the backing plate and pad. The cushioning effect prevents rotor vibrations from passing through the pad to the steel backing plate and caliper.

An exclusive "ionic bond" fusion technology is used to join the pad to the backing plate. When the pads are manufactured, the steel backing plate is coated with a metalized ceramic adhesive. The friction material is then pressed down on the plate and baked in an oven to cure the adhesive. This causes the ceramic to diffuse into the plate and pad underlayer creating a super strong bond that can withstand the most extreme braking conditions. In other words, you don't have to worry about Bosch pads ever "letting go."

LASER BURNISHED
When brake pads emerge from the oven, they are not yet fully cured. Residual chemicals and gases are still present in the friction material resin that must be removed before the pads are completely stable. Many aftermarket brake pads are sold in a "green" state (not fully cured) and require an initial break-in period after they have been installed. The risk with this approach is that too much heat too quickly can glaze and ruin the pads. If the customer doesn't take it easy on the brakes for the first few hundred miles of operation, he may not be happy with the results.

Nobody wants comebacks or dissatisfied customers, so Bosch pads are fully cured at the factory with a patented laser burnishing process. A precisely controlled laser beam is used to heat and condition the pad surface, eliminating the need for a traditional break-in period on the vehicle following installation. Bosch pads are ready to go from the very first stop.

DOING A COMPLETE JOB
When you're installing Bosch Premium Brake Pads, you should do everything else that's necessary to ensure your customer's brakes are safe and dependable. "Pad slap" brake jobs (replacing the pads and nothing else) only invite trouble down the road.

If the front disc brake pads are worn and need to be replaced, chances are other components in the brake system may require attention too. The most obvious ones would be the front rotors and calipers. But the rear brakes may need work also.

A quality brake job should cover every aspect of the system from the master cylinder to the calipers and wheel calipers. This includes:

• Checking the level and condition of the brake fluid (changing the fluid is recommended to get rid of moisture contamination).
• Bleeding all the brake lines to removed trapped air.
• Inspecting the entire system for leaks (hoses, lines, wheel cylinders, calipers and master cylinder).
• Inspecting all the mechanical and hydraulic components in both the front and rear brakes (calipers, caliper hardware, wheel cylinder, drum hardware and parking brake).
• Replacing the front and rear linings (if necessary).
• Inspecting and resurfacing or replacing rotors and drums as needed.
• Inspecting wheel bearings (repacking on older vehicles).
• Lubricating all critical areas such as caliper slides and shoe pads with moly-based high temperature brake grease.
• Checking and adjusting the parking brake.
• Checking the ABS system (no warning light or trouble codes).
• Making sure the pedal is firm, the brakes operate properly, quietly and provide safe stopping power once the job is complete.

There's no excuse for not inspecting each and every component in the brake system. Any parts that are out of specification, worn or damaged should always be replaced to restore brake performance and safety to like-new condition.

BRAKE ROTORS
New disc brake pads require a clean, smooth, flat surface on the rotors otherwise brake performance will suffer. A rough surface will accelerate pad wear and increase the risk of noise. An uneven surface or variations in rotor thickness can cause vibrations, noise and annoying brake pedal pulsations.

Unless the rotors and drums are in near perfect condition, resurfacing should be considered a must to restore the friction surface. There should be no deep scoring or cracks, runout should be less than .003 in. (.060 mm), and thickness variation should be less than .0003 in.

When rotors are resurfaced, care should be used to minimize runout. This may require measuring hub and rotor runout on the vehicle using a dial indicator (and indexing the rotor on the hub to minimize runout or installing a tapered shim behind the rotor to correct runout), or using an on-car lathe that cuts the rotor true to the hub. Ideally, rotor runout should be less than .001 in. on the vehicle or on a bench lathe.

Measuring rotor thickness is an absolute must. If rotors are worn to less than the "discard" specification marked on the rotor, the rotor must be replaced. If the rotor cannot be resurfaced without exceeding the minimum "machine to" thickness specification, replacement is also required.

It's the same situation with drums. They must be measured when the linings are replaced. If the inside diameter of a drum exceeds maximum specifications or it can't be resurfaced without exceeding the maximum "machine to" limit, it must be replaced. Also, both drums should have about the same amount of wear. If the difference is greater than about .040 in., both drums should be replaced even if only one is at or near the discard limit.

It's the same for rotors. If rotors have hard spots (look for discolored patches on the rotor surface), replacement is the best repair option. Changes in metallurgy extend below the surface. Turning the rotor may temporarily restore a flat surface, but the harder metal will still be there and cause the rotor to wear unevenly. Within a few thousand miles the pedal pulsation will return.

HYDRAULIC COMPONENTS
Calipers and wheel cylinders should be checked for leaks, severe corrosion or damage, and rebuilt or replaced if a problem is found. Pay close attention to the condition of dust seals and piston boots.

If a caliper or wheel cylinder is being rebuilt, do not reuse corroded steel pistons. Replace with new ones.

If a master cylinder is leaking externally or internally (pedal slowly sinks to floor), it must be rebuilt or replaced. Rebuilding aluminum master cylinders is not recommended.

Brake hoses in today's brake systems may have to withstand pressure of up to 2,500 psi so make sure there are no cracks, bulges or damage to the hoses.

The type of brake fluid required will depend on the vehicle application. Always follow the vehicle manufacturer's recommendations. Most domestic and Japanese cars and light trucks require DOT 3 fluid while most European cars use DOT 4. But there are exceptions, so make sure you find out which type is required. DOT 5 silicone fluid should never be used in any vehicle equipped with ABS.

BRAKE HARDWARE
Inspect caliper slide pins, bushings, sleeves, springs and shims for corrosion, damage and wear. Replace defective hardware as needed. Uneven pad wear can result if a floating caliper hangs up and isn't free to move sideways on its mounts.

As for drum hardware (self-adjusters, return springs, shoe springs, etc.) anything that is worn, damaged or badly corroded should also be replaced. If a return spring or shoe spring is stretched or discolored, it has probably suffered heat damage and must be replaced.

The cost of new springs and other brake hardware is only a small portion of a complete brake job. Replacing it can reduce the risk of comeback and assure the best possible performance out of the new Bosch pads you just installed.

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