Was at Home Depot yesterday, looked under the hood of a 100 series John Deere mower. It had the "John Deere Easy Change™ 30-Second Oil Change System" installed, which means you just change the filter every 50 hours. The new filter comes with oil pre-installed, so you just change the oil filter every 50 hours. Likely never changes all of the oil, and just tops up the oil additives. According to the FAQ, you can still drain all the oil via the drain if you want to, but its not necessary.
More info, pictures, and a movie at the website. https://www.deere.com/en/mowers/lawn-tra...0d-c6c00e6550d4
From the website-
"Draining engine oil is so 2017.
The engine modifications and new technologies are in. The re-envisioned oil filter with a media designed to resist breaking down in oil over time is here. The thousands of hours of testing are done. The end result is an all-in-one, oil and oil filter system like no other. The first of its kind. And thanks to the new John Deere Easy Change™ 30-Second Oil Change System (“System”), you’ll never have to drain the oil from 100 Series Riding Lawn Tractors1 again.
Here’s why: The new System captures contaminants and recharges your engine with nearly a quart (0.8qt) (0.76 l) of new oil. In fact, this System increases the amount of oil in the engine by nearly 40%.2 Your engine likes that.
What do you mean, I will never have to drain oil from my engine again? How is that possible? The answer is simple. We have developed a better filtration system and filter design for our 100 Series Riding Lawn Tractors1. This fully synthetic filter media has greater surface area which increases its capacity to hold harmful contaminants. What’s more, the filter media is designed to resist breaking down in oil over time. Which means you’ll get a cooler running engine. And a cooler running engine and better filtering helps increase engine oil life. John Deere's recommended oil service for 100 Series Riding Lawn Tractors1, is to change the System every 50 hours or once a season, whichever comes first. Remember, the System replaces a portion of your engine oil. And that's plenty.
The System uses John Deere Turf-Gard™ Oil. Using John Deere Turf-Gard™ Oil ensures you are using the exact oil specified by John Deere engineers.
Testing. Testing. Testing. Thanks to thousands of hours of rigorous and extensive testing, you can feel confident your engine will run for years to come.
1The John Deere Easy Change™ 30-Second Oil Change System is available on E120, E130, E150, E160, E170 and E180 Lawn Tractors today.
2Compared to similar V-Twin engine models that do not have the John Deere Easy Change™ 30-Second Oil Change System. That includes equivalent Deere 2017 models and 2018 models without the System.
Frequently Asked Questions:
What is new with John Deere Riding Lawn Equipment?
We are excited about the exclusive John Deere Easy Change™ 30 second oil change system. Exclusive to John Deere and only available on certain models of the new 100 Series Lawn Tractors. These tractors are designed for ease of use for both operation and maintenance. The John Deere Easy Change™ System (“Easy Change”) allows the user to easily complete the recommended engine oil and filter maintenance in 30 seconds."