* If it has a Turbo-Hydramatic 350 (TH350) automatic transmission: These typically used Type A ATF (Automatic Transmission Fluid). However, later in the life of the TH350, Dexron fluids became more prevalent. Dexron II or Dexron III would be a suitable replacement *if* your owner's manual doesn't specify otherwise. Using the wrong fluid can severely damage the transmission.
* If it has a Powerglide automatic transmission (less common in '72): This older transmission used a different type of fluid. You would need to consult a specialist or a repair manual specific to the Powerglide for the correct fluid.
* If it has a manual transmission: Manual transmissions use gear oil. The specific type and weight would again be in your owner's manual, but likely something like SAE 90 or similar.
Crucially: Don't rely solely on this information. Find your owner's manual (or a reproduction online) to confirm the correct fluid type and specification for your particular Caprice. Using the incorrect fluid can ruin your transmission.