Ji Sung-Park added a fourth in the 68th minute, having earlier set up the third for Swedish striker Hiljemark.
PSV moved two points clear at the head of the standings on 15 and remain the only unbeaten side after seven rounds. Ajax stay on 11 points, amid a cluster of clubs.
Ajax, allowed no supporters in the Philips Stadium after a ban by the city of Eindhoven, also lost 4-0 at Barcelona in the Champions League in midweek.
PEC Zwolle were deposed from top place after losing for a second successive week, this time 3-0 at Vitesse Arnhem for whom Brazilian teenager Lucas Piazon, on loan from Chelsea, scored twice.
PEC had been the surprise early leaders through the first six weeks of the season but coach Ron Jans was philosophical about the end of their unexpected run.
"We were beaten in the key phases and duels but I don't think we need to panic, just continue doing what we were doing," he told Dutch station Radio 1.
Feyenoord, after their worst start to a season, won a third successive match as they continued to turn around their fortunes with a 35th-minute goal from 18-year-old Tonny Vilhena settling their home match against FC Utrecht.
The Rotterdam-based team moved up to eighth place, with 10 points from seven matches.
NAC Breda also look to be putting a slow start to the season behind them as they won a second successive game, a convincing 3-0 home triumph over AZ Alkmaar.