Jackson tallied 21 disposals to go with 48 hitouts, 10 clearances and three goals in the 16.8 (104) to 9.9 (63) win in front of 37,570 fans on Thursday night.
Treacy, who entered the match on the back of a three-game goalless run, finished with three majors to go with crashing pack after pack.
Fremantle's fifth win on the trot improved their record to 9-5 ahead of next week's home clash with St Kilda.
Essendon (6-8) face a major battle to turn around their fortunes, with their fourth consecutive loss leaving them well adrift of the top eight.
Jackson dominated his contest against Essendon debutant Vigo Visentini, who battled hard for 15 disposals and 17 hitouts but was outclassed by Fremantle's star big man.
It continued a rich vein of form for Jackson, who has thrived in the lead ruck role this season, especially in the games when Sean Darcy isn't playing.
"He's a special player. We love having him. He's not going anywhere," star Fremantle midfielder Caleb Serong told Fox Footy.
"He's locked in with us. I think what him and Sean are going to build over the next couple of months is really exciting.
"I can't wait to be a part of it. As a midfielder, I'm licking my lips."
Serong also had a big night with 35 possessions, seven clearances and two goals.
Dockers veteran Nat Fyfe, who spent the previous two matches as the sub, was given a start but tallied just three first-half disposals on the way to a total of 11 for the game before being subbed out early in the final quarter.
Jye Caldwell (32 disposals, eight clearances) and Darcy Parish (31 disposals, six clearances) racked up big numbers for Essendon, while Nate Caddy showed flashes of brilliance - including a spectacular grab in the second quarter - on the way to 15 disposals and a goal.
Fremantle's four-goal burst to start the second quarter broke the game open after a tight opening term, and it also led to plenty of spice.
Former Bomber Patrick Voss was clearly fired up, and at one point he was left to fight off three Essendon players - Andrew McGrath, Jayden Laverde and Angus Clarke.
After Voss was involved in another skirmish, this time with Nic Martin, Fyfe came in to try to cool down his teammate.
Shai Bolton was also keen to get into the face of Essendon players, but Essendon fed off the higher emotion to cut a 29-point deficit back to 16 by half-time.
Essendon subbed out Xavier Duursma at half time with hamstring tightness, opening the door for sub Archie Perkins to impress.
There were two critical moments in the third quarter that shaped the contest.
First, Perkins took his eyes off the ball and fumbled what should have been an uncontested mark for him inside 50m while running with the flight of the ball.
A few minutes later, Fremantle's Nathan O'Driscoll put his body on the line to make a key spoil while running with the flight of the ball himself.
O'Driscoll's bravery led to a Serong goal, sparking a run of three straight majors for Fremantle as the lead blew out to 37 points by the final change.
Visentini was Essendon's 11th debutant of the year, and the Bombers fielded seven first-year players against the Dockers.
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