The radiator petcock drain on a 1999 Pontiac Bonneville is on the bottom of the radiator. Look for a small black plug that looks like the plug found on a thermos or cooler.
drain is on the lower side of the radiator opposite of the fill neck. You will need to remove the splash shield from underneath the car to view the petcock. check out www.pontiacbonnevilleclub.com for more info.
Look at the bottom or rear of the radiator
The 2003 Chevrolet Cavalier radiator drain petcock is located on the bottom of the radiator. The drain will be towards the right side of the radiator.
I have a 2000 Pontiac Grand AM and radiator drain cock is located at the lower/front (not bottom) at the curbside of the radiator, you will need a hex key to back out petcock.
drivers side bottom right of radiator remove shield and look for plug
Is there not a drain petcock on the bottom of the radiator?
Look closely at the radiator. Check the bottom corner of the radiator that is opposite of the lower radiator hose. If there is no drain plug or petcock, then the coolant will need to be drained by removing the lower radiator hose.
Should be a drain plug or petcock at the bottom or rear of the radiator or remove the lower radiator hose The petcock or drain plug is located on the driver's side at the bottom of the radiator. Turn it counter-clockwise to drain.
Radiator drain plug. Located at the bottom or lower side of the radiator used to drain coolant from the radiator.
Open the radiator petcock and drain coolant into a container. Dispose of all coolant properly as it is toxic to animals. Close petcock and fill system with water. Run the engine for several minutes with the heat on high. Drain the system again. Several repeats of this procedure will flush the radiator and engine for the Firebird.
Petcock on bottom or radiator or remove lower hose.
To drain the radiator when it is time to change the coolant.