Also transmission oil, or MMO.
This was a thing in the 2000's with GM's AFM cold-sticking piston rings in the 4 shutdown cylinders.
I had one of those, and with synthetic oil they stuck ~ 70k miles and turned the engine into an oil pumper. It pumped a quart per 1,000 miles out the exhaust after using none prior, per dipstick levels. I tossed in some ATF and it cleaned enough to near stop oil consumption.
Those using mineral oil reported oil pumping starting ~ 30k miles.
That's when I dumped my Chevy and got 2012 Ram. Then I found out about cam failures.
I recall vividly back in the day when my best bud's dad used to put his 66' Monaco ragtop away for winter storage...
(He put a 440 crank and 440 heads on his 383 and tickled up the 727TF trans, and straight duals out the back. Don't know the rear end, but it would lay hard 11's down the road forever!)
He would change the oil & filter, fill the tank and put gas-line antifreeze & fuel stabilizer in there... run it for a good boot in the neighborhood to operating temp, and then have his son or me hold the gas pedal down while he dumped transmission fluid down the carb until it choked out.
Then he'd cover it and walk away until late spring.
I have such great memories in that car. My and my Bud would be in the back with his Brother, and his Dad, Fester (his nickname as he looked like Fester Adams, but with hair!) was behind the wheel and his Mom in the front seat.... He'd take us out and rocket ship that car everywhere, shifting the 727TF up and down all the time....and always had his bottle of sip-n-sherry under the seat for frequent hydration needs..lol.
When we were teens and after his Dad passed but left him the car, we would have great drives in that car.
One time in Port Hope we were..ummm... hydrating whilst driving.... and coming down a country hill at over 100mp/h and saw the stop sign and cars on either side taking their turns through the intersection... My Bro stood on that huge break pedal to try and stop it...we blew through the stop sign with all four wheels bellowing smoke out of them.
Trying to stop an over 2-ton ragtop with four-wheel manual drum brakes and asbestos shoes was not easy....
Ahhhhhhhh...the good ole' days!