A fluid level measuring system for machines which utilizes fluids and has rotating and/or reciprocating elements. The system receives data from sensors as to the measured fluid level and measured fluid temperature. Optionally, data is received from other sensors such as to the angle of inclination of the machine, gear setting (for a transmission), idle speed (for an engine or transmission), and dielectric constant of the fluid. The measured data is stored in a first data storage device. A second data storage device contains data as to the recommended fluid level and acceptable deviations thereof based upon a variety of possible sensor readings, which can be obtained from sources such as the manufacturer of the machine or by controlled dynamic measurements. A processor compares the stored sensor readings to the data stored in the second memory to arrive at the operational fluid level. The processor controls a display to identify the operational fluid level to the operator. Optionally, the processor may determine whether or not to initiate a change in the fluid level and/or activate an alarm. One application of the fluid measurement system is identified for a transmission.