Ibrahim al-Hajari said: We had Abdullah bin Abi Awfa (may Allah be pleased with him) lead us in the funeral prayer of his daughter. He said four takbirs, then remained silent for a while. We thought he might say a fifth takbir; then he gave the salam to his right and his left. When he finished, we said: What was this? He said: I will not do more than what I saw the Messenger of Allah (peace and blessings be upon him) doing; he (peace and blessings be upon him) used to do it like this, or he said: he (peace and blessings be upon him) did it like this. Then he mounted his riding animal and said to the servant: Where am I? He said: In front of the funeral. He said: Did I not forbid you? He had become blind.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6988
It is narrated from Sayyiduna Abdullah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) used to do three things which people have abandoned; one of them is giving the salam of the funeral prayer like the salam in the prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6989