i am assuming you have an auto since you said you pulled over and checked the fluid level, the power loss could have been cause by the torque convertor sliping excessively, if that was happening the O/D OFF light will flash, meaning that the PCM has detected a problem with the transmission, and there is a code to be read. you need to get a tranny shop to read the code unless you have a code reader that you can drive around with hooked up, and when the light flashes, read the code then, these codes are not stored in memory

98.5 Black SE ATX S&B filter, SVT MAF, optimized SVT TB, mesh grille, removed orange reflectors, painted rear reflector, gutted pre-cats, optimized SVT LIM, 19lb injectors, resonator removed cant afford an svt but lookin for 1 in nc