What type of detergent should I use in this front loading washing machine?

You should use powder detergent only for this front loading washer. Do not use solvents such as benzene, and do not exceed the maximum fill line in the detergent drawer. Using too much detergent can cause excessive suds, which decreases washing results and may cause heavy load on the motor leading to malfunction. Adjust detergent usage based on water temperature, water hardness, and load size. (Page 12)