* TH350 3-speed automatic: This was a popular choice across various engine options.
* SM465 4-speed manual: A robust manual transmission often paired with V8 engines.
* Saginaw 3-speed manual: A less common manual transmission option.
To know the exact transmission in a *specific* 1980 El Camino, you'd need to check the vehicle's documentation (like the original owner's manual or the vehicle identification number (VIN) decoder).