With former Montgomery County police Chief Robert J. diGrazia gone less than a week, the department's new leaders have already begun to do away with some of the hallmarks of the ex-chief's administration. It is an effort they say, to "get back to basics" in policing.

Already scheduled for elimination is the department's three-man management audit and evaluation office, whose work diGrazia had placed special emphasis on. The sivision investigated various other divisions in the department to see whether they were operating properly, and then made recommendations for improvement to the chief.

DiGrazia was fired last Thursday by County Executive Charles W. Gilchrist, who said the ex-chief had become "ineffective" in part because of his persistent "disparaging" remarks about police officers that strained his relations with the officers. DiGrazia is appealing his firing.

The new acting chief, Donald E. Brooks, said the audit division is "a luxury I can't afford" at a time when there is a "severe shortage" of high-ranking officers for supervisory duties.

Yesterday, the two captains who worked in the audit division were answering phones in the acting chief's office.

Brooks also said he is planning to revitalize a dress code for the officers. So far, he has asked the high-ranking officers to wear the traditional green uniform coat, called a blouse, which diGrazia had decided to do away with because he thought it was a wasted of the department's money.

"I feel as though a reasonable grooming standard and dress code goes along with good discipline," Brooks said. "The men have more pride in themselves when they wear their uniforms well."

In one major personnel change in the department, Philip H. Marks-the civilian whom diGrazia brought with him when he moved to Montgomery from the Boston police department in 1976, and who was one of the exchief's closest advisers-has been stripped of his authority over several key divisions in the department.

Marks will now oversee a limited number of "special projects," such as development of a new promotional exam for sergeants, that were started under diGrazia and that the new administration wants to keep, according to Maj. Wayne Brown.

Brooks has put Brown in charge of the day-to-day operations of the department. Brown and Brooks are the two highest ranking officers in the department. A third major, Thomas Thear, decided to retire after diGrazia was fired. Thear was placed on administrative leave.

Both Brooks and Brown applied for the chief's job in 1976, but diGrazia was chosen over 110 others.

Brooks, in marked contrast to diGrazia, has expressed concern that there is a need for more top-level officers. When diGrazia came to the department he set about cutting back on the "top brass." He never filled the position of lieutenant colonel, which was the rank second to the chief, and he eliminated one major's position.

DiGrazia also tried to fire Brooks when he first came to the county. But now retired county executive James P. Gleason intervened on Brooks' behalf and the major stayed.

The idea of reissuing a grooming code and of fostering a pride in the uniform, are part of the new tone Brooks says he wants to set for the department.

Several officers have said that Brooks and Brown want to make a concerted effort to keep the department "out of the headlines." DiGrazia often made headlines with his views about policing and his sometimes disparagingremarks about police officers.