The transmission fluid needed for the 1989 Chevrolet K1500 with
a manual transmission is Synthetic Synchromesh transmission fluid
(5W-30) (MTFQT). If the transmission you have is the MG5 5-speed,
the capacity is 4.2 pints. If the transmission is the SM465/M20,
the capacity is 8.5 pints.
The 1989 Cutlass Ciera modern production spark plugs are
pre-gapped from the factory and should not be altered. The OEM AC
Delco Professional Platinum #41805 for this engine comes pre-gapped
at .045 inches for reference purposes.
Any Dextron II compatible fluid will work. The back of the
bottle will show compatibilities. The capacity is 3.2 quarts, same
as the crankcase (engine oil) capacity. Do not use engine oil, that
is for MANUAL transmissions only.