Tech Tip: Low Or Spongy Pedal After Routine Brake Service
Some vehicles may exhibit a low or spongy pedal after wheel end brake service that cannot be remedied by bleeding the brakes. This may be due to a prematurely deteriorated seal in the master cylinder. Remove snap ring and rearmost piston from master cylinder to inspect seals. If any deformation or deterioration of seals is present, replace the master cylinder.
Master Cylinder Service On 2005-2009 Saab 9-7X
Some owners may complain of a squeaking noise when applying or releasing the brake pedal. According to Saab, the problem is contaminated brake fluid. The contaminated fluid may swell the master cylinders piston seals.
ASE A5 Prep: Electronic Brake Distribution (Video)
Anti-lock brake systems (ABS) and the HCU are replacing proportioning, combination and other valves to change the braking forces in the front and rear. This is called Electronic Brake Distribution (EBD) and it can dynamically change to proportioning to take into account if the vehicle is turning or is loaded. The system can also use EBD to perform a “soft stop.” This routine is performed when a vehicle is slowing at low speeds and the brake force is varied in the front and rear so the vehicle’s attitude is controlled and weight is evenly transferred. This means a flatter and more stable stop.
What DOT Really Means: Brake Hose Inspection And Replacement
Brake hoses are the most government-regulated components on a vehicle. Anyone making brake assemblies must be registered with the Department of Transportation (DOT). All aftermarket hose, fittings and complete hoses must conform to FMVSS 106 and SAE J1401. These tests are demanding and often exceed what a vehicle will see in the real world.
Drum Brake Service: Single-Anchor, Floating Shoe Designs
Although four-wheel disc brakes currently dominate the import brake service market, millions of drum brakes are serviced each day in independent import shops. Thanks to their age, many drum brakes present problems related not only to normal wear, but also to extended age and mileage.
ABS/ESC Brake Solenoid Diagnostics
The ABS computer or HCU is a node on a high-speed vehicle bus. This means that the information can be typically accessed through the OBDII DLC. The ABS controller/modulator is the heart of any ABS or ESC system. The modulator gets the brake pressure from the master cylinder. Inside are the valves and solenoids that control the pressures to the wheel. During normal operation, the pressure from the master cylinder goes through the HCU unaltered.
Brake Job On 2006-Current Cadillac DTS
The 2006-current Cadillac DTS is the largest sedan that General Motors offers. The DTS incorporates the K-platform as denoted by the 4th letter in the VIN. It is built on the same line as the Buick Lucerne. The two vehicles share many brake components, but option packaging is different for the Lucerne.
Memory Lane: Nuts, Bolts And Screws – Finishing A Chevy Restoration Project
Gary Goms discusses the mechanical challenges of restoring a truck that he began maintaining when he went to work in a gas station – back in 1957!
Brake Job: 2000-2007 Ford Focus
The 2000-2007 Ford Focus is based on the Ford global C1 platform, shared with the European Ford Focus and Volvo S40. Nothing is really groundbreaking about the brake system. However, not paying attention to the details can end in a post brake job comeback.
Inspecting Brake Hydraulic Systems: Worn Components Take Their Toll on Advanced Suspension Technologies
During a service writer’s efforts to sell competitive brake services at the service desk, he or she often focuses on selling “good, better or best” brake friction replacements, while ignoring the added expense of repairing brake hydraulics. Did you know that neglected brake system hydraulics can cause an expensive warranty comeback?
Brake Myths Revisited
The overall response to the Eight Brake Myths Busted article in the January issue was huge. I took a lot of abuse, but that was the goal of the article. Too many times technicians get stuck in a mindset that leads to false diagnoses. The point of the article was to shake things up in
Advice from the Bendix Answerman: Brake Fluid Service as Important as Oil Changes
While some may think an old school “flush” will breathe new life into a braking system, Chuck Kennedy, technical trainer at Bendix Brakes says if one is performed without checking for contaminants already present, the braking system’s hydraulic control unit (HCU) can be seriously damaged. That’s why maintaining clean, contaminant-free brake fluid is just as important to a vehicle as getting regular oil changes.