Salam. But we don't rely on oral traditions alone. And as I mentioned in an earlier e-mail, there is a well-developed 'science of hadith' involving close examination of the trustworthiness of the transmitters in the chain of transmission of the Ahadith. Many, many Ahadith have been rejected on the grounds that there isn't a reliable chain of transmission. So it hardly bears resemblance to the caricature you paint it out to be.
'Ulm-ul-Hadith' developed by fallible human . ALLAH , swt , only promised to preserve and guard the Qur'an and nothing else . No wonder why you see hundreds and thousands of fake Hadith in the name of the Prophet . Even Bukhari and Muslims are also full of fake Hadith and lies . Sunni canonized them as 100% Sahih as if it is Qur'an , while you have this ( for an example per se ..):
Bukhari Volume 7, Book 72, Number 787:
Narrated Anas bin Malik:
The Prophet was neither conspicuously tall, nor short; neither, very white, nor tawny.His hair was neither much curled, nor very straight. Allah sent him (as an Messenger) at the age of forty (and after that) he stayed for ten years in Makkah, and for ten more years in Medina. Allah took him unto Him at the age of sixty, and he scarcely had ten white hairs on his head and in his beard.
==>> 60 years.
Bukhari Volume 5, Book 58, Number 242:
Narrated Ibn Abbas:
Allah's Messenger started receiving the Divine Inspiration at the age of forty. Then he stayed in Makkah for thirteen years, receiving the Divine Revelation. Then he was ordered to migrate and he lived as an Emigrant for ten years and then died at the age of sixty-three (years).
==>> 63 years .
Muslim, Book 030, Number 5805:
'Ammar, the freed slave of Banu Hashim, reported:
I asked Ibn 'Abbas how old was he when death overtook the Messenger of Allah (may peace be upon him). He said: I little know that such a thing is not known to a man like you who belong to his people. He said: I asked people about it but they differed with me, and I liked to know your opinion about it. He said: Do you know counting? He said: Yes. He then said: Bear this in mind very well that he was commissioned (as a Prophet) at the age of forty, and he stayed in Makkah for fifteen years; sometime in peace and sometime in dread, and (lived) for ten years after his migration to Medina.
==>> 65 years .
I don't know where the original manuscripts of Sahih Bukhari and Sahih Muslim are, no.
Ws.
Nobody knows my brother , because they don't exist . But we rely for our religion upon these two books mostly if it is not entirely !! So vulnerable our religion is !!