Manual transmissions are being discussed. Technician A says that if it requires gear oil, to always use GL-5 rated oil to protect the synchronizers. Technician B says that if it requires engine oil that you should add a friction modifier to it. Who is correct? A. Technician A B. Technician B C. Both Technician A and B D. Neither Technician A or B

The correct Technician is;

Technician B

Explanation:

API GL-5 gear oils does not meet transmission oil specifications as an API GL-5 oil can produce up to 400% the amount of copper observed when used oil is carried out than GL=4 gear pols, such that the synchronizers in transmission having synchromesh are made ineffective due to wear

Friction modifiers changes the amount of friction between transmission components and engine components.

When friction modifier are added to engine oil used in manual transmission,  it reduces the friction by modifying the friction coefficient of surfaces in contact and moving in relation to each other such that wear is reduced

Modern manual transmission engines require more protection than the manual transmission of older car engines which includes the presence of friction modifiers

Therefore, only Technician B is correct.