Aoa, rizwan bhai. I recently visited kalam and mahdund lake. We take our personal cars (airwave & carolla) till kalam. The road is good with slight traffic till Bahrain after which it is totally broken till kalam. Usually 4*4 is recommended but we somehow managed to kalam by driving in motions on high ends.
If you have any good condition car i.e 1300cc or + then its recommended otherwise not.