My check engine light come on and then I notice that overdrive light is flashing the truck seems to be running fine what could be the problem with it
Not necessarily. The fault could easily be in an engine control system that "indirectly" affects transmission operation. The best thing to do is download the diagnostic trouble codes which will give a general indication of he fault but to actually resolve it a diagnostic has to be performed, that is individual components have to be tested. If you request a check engine light diagnostic a certified mechanic from YourMechanic would use a code scanner to retrieve the diagnostic trouble code(s) from your car’s PCM (that is, the specific codes have caused the light to set) and then test the appropriate individual vehicle components or sub-systems (often a sensor, circuit, and the like) to pinpoint the reason why the check engine light has illuminated. Once the faulty part or component is identified, it is explained to your satisfaction and the mechanic will let you know of the cost to repair. If you schedule the recommended diagnostic, the mechanic will resolve this promptly for you and all on a mobile basis right at your location. If you have further questions or concerns as you decide what to do, do not hesitate to re-contact YourMechanic because we want you to make the most of your repair dollars and help you get the best possible results.