I’m pretty new to working on cars. I read my 2001 Sonoma takes 12 quarts of coolant. I’m flushing the radiator and I can see there’s much less than that draining. Maybe a gallon and a half tops came out and about the same went in when I went to flush it.
Where is the rest of the fluid? I’m assuming some of the 12 quarts goes into the reservoir, but where is the rest at?
Just an FYI… that drain Tester showed… I’ve seem machine shops with tools and torches not be able to get those out with the block on the bench. You getting it out IN this 19 year old car is 99.9% impossible.
Is it not necessary to do? I’ve seen multiple videos on youtube with people flushing their systems with chemicals and not one used the engine drain plug. I would think that not draining it would result in a lot of the chemical flush being left in the engine as well as excess water.
According to the factory manual, if only draining the radiator, up to 40% of the coolant will remain in the system. The heater system may hold some coolant too. Capacity of the 4.3 with auto trans. is about 13.8 qts. Below is a rudimentary depiction of the block drain plugs on each side.