According to Mercedes' preview for this weekend's Brazilian Grand Prix, the team will use that race and the season finale in Abu Dhabi as “the first two test opportunities ahead of the new season, trialling new and interesting concepts”.
It declared that it would “become a little bolder”, test new parts and carry out “experiments” that would be too risky if it was still fighting for titles.
Mercedes motorsport boss Toto Wolff said, “It might be tempting to think that, with both championships now secure, the pressure is off for the two remaining races of 2017. That couldn't be further from the truth.
“Inside the team, we are looking at the next two race weekends as the first two grands prix of 2018.
“We have two races that we are determined to win in order to take that positive momentum into the winter.
“There will be no backing off just because the championship business is now done.”
Lewis Hamilton clinched his third title in four years with Mercedes in the Mexican Grand Prix two weeks ago.
His new-for-2017 team-mate Valtteri Bottas trails Vettel by 15 points in the fight to finish second in the drivers' championship.
“Lewis is operating at the peak of his powers right now, and will be determined to add another victory to last year's success,” he added.
“Valtteri made a promising step forward in Mexico and will aim to build from this at Interlagos.
“As recent rounds have shown, winning grands prix is never easy.
“Red Bull have taken two victories in the past four races and, although we have claimed the other two, Ferrari remain formidable opponents.
“With the championship now settled, the battle for 2018 has already begun.”
The Brazilian Grand Prix weekend runs from November 10-12 (local time).