Call a GM Dealer's service center. They will know.
Do you mean "change THE transmission" or "Change the transmission FLUID"? Big difference there....
The 198 Buick Skylark was offered in a 2.5L L4 and 3.0L V6. Both power-train options were provisioned for automatic transmission fluid through the dipstick/tube assembly.
Gool ol' Dexron.
It is the transmission cooler hose or line. It runs the fluid through a cooler on the radiator to cool the transmission fluid.
Dexron III, but check with any auto store first.
To change the transmission fluid in a 1972 Buick Skylark, first, ensure the vehicle is parked on a level surface and the engine is off. Remove the transmission pan bolts and carefully lower the pan to drain the old fluid. Replace the filter and clean the pan before reinstalling it with a new gasket. Finally, refill the transmission with the appropriate type of fluid through the dipstick tube, checking the level as you go.
The 1992 Buick Regal transmission has a fluid capacity of 6.3 quarts. You can check the transmission fluid level with the transmission dipstick.
7.4 quarts of Dextron VI, do not overfill
5 to 7 for a fluid change Add 3 to 5 for a rebuild.
You have to take the transmission pan off, change the filter/fluid/gasget make sure you put all the bolts in first befor you titan the bolts up.
Check of change fluid and filter--if this doesn't help it may be time for a rebuild
Maybe use some kind of siphon pump... It would be a complete mess trying to remove the transmission oil pan. Or maybe just go in and get a fluid change.