2:36 PM PT -- Officials tell us the body has now been identified and the autopsy is complete.
The medical examiner has determined the cause of death was multiple blunt force trauma.
Autopsy results for OKC Thunder co-owner Aubrey McClendon are delayed because medical examiners are having trouble ID'ing the badly charred body... TMZ Sports has learned.
A rep for the Oklahoma state coroner's office tells us they had to bring in a forensic odontologist ... a dentist who can help identify human remains by teeth.
McClendon crashed his car into a bridge on Wednesday ... and Captain Paco Balderrama of the OKC Police Department told us the body was "heavily incinerated" because the car burst into flames.
The coroner must officially identify the body as part of the investigation ... which is ongoing.