The incident occurred at about 5pm when the seven in the vehicle were returning from a funeral in Idutywa and heading to Cape Town.
Police captain Namhla Mdleleni said police were investigating a case of culpable homicide.
The three who died were among the 26 people who lost their lives in the province over the Black Friday weekend, according to the Eastern Cape transport department.
The department said many had also sustained injuries in the 17 crashes.
Pedestrians are said to have accounted for seven of the 26 people who died while there were 14 passengers and five were drivers.
Reckless and negligent driving, speeding and driving under the influence of alcohol are said to be the contributing factors that caused the accidents. Transport MEC Weziwe Tikana-Gxothiwe said the fatalities were a grim reminder that driver behaviour could lead to death.
“The fact that we have lost so many people, most of whom were at the prime of their lives, is of great concern. The fact that many died in head-on collisions which point to reckless and negligent driving, is of even greater concern.
“We call on road users, passengers, pedestrians and drivers to work with traffic officers,” Tikana-Gxothiwe said.
The MEC said law enforcement officers would be out in full force to deal with the high traffic volumes expected during the festive season.
The week before, 10 people died and others sustained injuries in accidents in the province which included an overturned vehicle in which five people died while 11 sustained injuries on the R409 road near Tsomo. Four also died on the R408 in Ngcobo location.