SCs **do not** unanimously call themselves dalit all over India. Eg in UP, the preferred word is bahujan, in Karanataka it is Adi Karnataka and in Andhra Pradesh it is, Adi Andhra
Dalit term mainly is used by the media and some vested interests. According to a survey by a US institute, conducted on what names SCs prefer to call themselves -- not one of them mentioned dalit.
"While most of the scheduled caste respondents gave their jati, a proportion recorded a generic name, but while harijan (or harizan or some other spelling) was used by 1351 respondents in 18 different states, and a number of respondents used scheduled caste, not one respondent chose dalit.