Do the GXP transmissions have and actual filter? Since it did spike up after 2 1/2 hours of driving from 181 to 196, there had to be a low flow condition or something that would cause this to happen. I had been monitoring the temp since it was higher than what I expected so it was something that resulted from a mechanical or cooling issue. Is there a temperature control valve or temperature regulating unit that could of temporarily stuck or malfunctioned indicated by the check engine light?
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