I drive a Toyota Progrès and it has been performing well until it clocked 140,000 kms. A series of problems started with the engine performance but the latest is the front brakes on both wheels jamming. How can I fix the issues?
Segane Tony.

Brake systems such as the one on your Toyota are operated using hydraulic pressure to actuate mechanical components which use friction to stop your wheels, once you apply the brakes. To identify the cause of jamming brakes on your car you must appreciate the role of the brake master cylinder, wheel slave cylinders attached to calipers and brake fluid. When your brake system jams, the pads or shoes on the discs it is more likely a result in the breakdown of the brake master or slave cylinders and the attached caliper system. An inspection of the master and slave brake cylinders is crucial to rule out leakages caused by damaged seals or jamming caused by corrosion damage. Where corrosion damage is found it would be a good idea to replace both front slave cylinders. The most likely cause of damage to the brake hydraulic system is the failure to carry out periodic two-year brake fluid maintenance. Besides providing hydraulic pressure, brake fluid also prevents corrosion damage and helps to cool down the hot fluid circuit.
Over time brake fluid accumulates moisture as you apply the brakes, this introduces destructive corrosion, reduces the hydraulic performance and lowers the boiling point of brake fluid which causes overheating and damage of seals and warping of metallic components. Renewing your brake fluid every two years will prevent this sort of damage to your Toyota or any other car.