Hi my name is***** will try to help. First inspect your filter internally by cutting it open using a filter cutting tool. Check for metal/debris that would indicate a transmission or internal failure occurring. If ok then the next step is to have your pressures tested to be sure they are within specs. This will help pinpoint whether you have a problem with a valve, and internal issue, or pump problem. If the mechanical checks test ok then you could have a problem with the shift selector itself, your harness, or the shift solenoids.
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