Our Sunni brethren's attitude towards such ahadith is influenced by their belief that the traditions of as-sihah as-Sittah (the six correct books of traditions), and especially those found in Sahih al-Bukhari and Sahih Muslim are all correct. Imam an-Nawawi writes in Sharh Sahih Muslim:
"The fact that the ummah has willingly accepted [the Sahih al-Bukhari and Sahih Muslim] has led us to the opinion that it is obligatory (wajib) to act on what is written in these two [books], and this is an unanimously agreed view. People are obliged to act on a khabaral-wahid (a hadith reported by a single narrator) found in other books only when its chain of narrators is correct; and even then it would not create but only a strong assumption. And the same applies to the two Sahihs; but these two differ from the other books in that all that is in these two is correct and there is no need to examine them; rather it is wajib to follow them unconditionally. But as for the ahadith in other books, they will not be followed until their credentials are checked and they are found to fulfil the conditions of a correct hadith."
This unconditional blanket acceptance of the ahadith found in these books has compelled our Sunni brothers to accept the theory of abrogation of recital (naskhut-tilawah); that is, they believe that recital of some verses was abrogated although the law contained in some of them continues. Two well-known examples of such supposed verses are the so-called verses of stoning (rajm) and of ten or five sucklings, which are found in Sahih al-Bukhari and Sahih Muslim and other books. 
And the hadith of Sahih Muslim explicitly says:
"Ummu 'l-mu'minin 'Aisha said, "There was among what was revealed of the Qur'an (the verse) 'Ten known sucklings create prohibition' (i.e., foster relationship). Then it was abrogated by 'five sucklings', and the Messenger of Allah expired and they were among what was recited of the Qur'an." 
Ibn Majah has narrated another hadith from 'Aishah which explicitly says that the two verses were lost after the death of the Prophet. She is reported to say: 'The verse of stoning and of suckling an adult ten times were revealed, and they were (written) on a paper and kept under my bed. When the Messenger of Allah (s.a.w.) expired and we were preoccupied with his death, a goat entered and ate away the paper. 
It needs no great intelligence to see that this theory of abrogation of recital cannot be of any use in such cases. If a surah or verse was recited in the life of the Prophet and then it was lost either because the reciters were killed in a battle, or because a goat devoured it or for any other reason, then the question arises: Who had the right to abrogate a Qur'anic verse after the Prophet's death? Had any other prophet come after Muhammad (peace be on him and his progeny)? That is why Sayyid al-Khu'i has said, "It is clear that the theory of abrogation of recital (naskhu 't-tilawah) is exactly the same as belief in alteration in and omission from the Qur'an." 
Therefore we have to strictly adhere to the well established principle
that any hadith going against the Qur'an must be discarded and 'thrown
to the wall' - if it cannot be reinterpreted in an acceptable way.
For the verse of stoning. see Sahih al-Bukhari, vol 4. p 179. 265:
Sahih Muslim,vol. 3. p. 1317: Musnad Ahmad ibn Hanbal, vol
1 (Beirut: al-Maktab al-Islami. 1969) p. 40: Sunan Ibn Majah, vol.
2 (Cairo edition) p 853: Muwatta, Imam Malik, vol 2.p 623.For the
verse of suckling, see: Sahih Muslim, vol. 4. p. 167: As-Suyuti,
ad-Durru 'l-Manthur, vol. 2. p.
Sahih Muslim, vol 1. p. 167: As-Suyuti, ad-Durru 'l-Manthur,
vol2. p. 135.
Musnad Ahmad bin Hanbal. vol. 6. p. 269: Sunan Ibn Majah,
p. 626: Ibn Qutbah, Tawil Mukhtalafi 'l-Hadith (Cairo: Maktaba
al-Kulliyat al-Azhariyya. 1966) p. 310 which has been misprinted as 210-:
As-Suyuti, ad-Durru 'l-Manthur, vol. 2. p. 13.
al Bayan , p. 224.