Is money acquired from raising the rental value of cars leased to companies, in order to increase the salaries of employees and drivers due to their insufficiency and work pressure, permissible?

If the money paid by the employer is specifically designated for car fares, then it is not permissible to spend it on anything else. The manager acts as an agent for the employer in delivering the money to its intended purpose, and he is not allowed to dispose of it in a way that contradicts his principal's instructions. Furthermore, low salaries and work pressure do not justify consuming wealth unjustly. Instead, one should demand a salary increase or a reduction in workload.