yes you are absolutely right till nar you can use any vehicle. however a short of 1-1.5 km from punjpeer you can also use a good road clearance car.
this track leads you to a final destination of a forest rest house. booking of which can be arranged from rawalpindi forest office at sawan camp.
the last track of approximately 1.5 km is jeep track. moreover you can also take another track which will take 30 min hiking to reach the top