Shlok 44

Sachudraha Krushnabhaktaa Ye Taistu Malordhvapundrake            |
Dwijativadvariye Nijadhasmeshu Sansthitaiha                                   ||44||

Shatanand explains that there are two types of Shudras - Sachudra (or Sat-Shudra) and Asachudra.  Shree Hari has defined a Sachudra as a Krushnabhakta and Nijadhasmeshu Sanstitaiha - one who is a faithful Krishna devotee and who is true to his duty.  Smrutis further explain:

Vishudhvanvayasamjato Nivruto Madhmaisataha                  |
Dwijabhakto Varigvrutiha Sachudraha Samprakirtitaha        ||

‘Those who are born in a righteous family, who refrain from meat and alcohol, who are devoted to Brahmins and who serve Vaishyas are considered as Sachudra.’  Those who do not live according to this code of ethics are considered as Asachudra.  A Shudra should be understood as a person of the fourth caste.

Shatanand explains a Shudra as any ‘low born’ and therefore is not exclusively a member of the fourth caste and as such a child born out of an affair is considered a Shudra.  However there are two types of children born - Anulomaja and Pratilomaja.  The following explains the various Shudras or low born.  The first are born out of Anuloma or true marriage and therefore are Sachudras.

Murdhavshakti - a child from a Kshatriya mother and a Brahmin father.  Ambashta - Vaishya mother and Brahmin father, Nishad or Parshav - Shudra mother and Brahmin father, Mahishya - Vaishya mother Kshatriya father, Ugra - Shudra mother and Kshatriya father.  Karana - Shudra mother and Vaishya father.

Now are explained those born from a Pratiloma marriage - Asachudras:

Suta - Brahmin mother and Kshatriya father, Vaidehic - Brahmin mother and Vaishya father, Chandal - Brahmin mother and Shudra father (such a Chandal is considered as lowest type), Magadh - Kshatriya mother and Vaishya father, Kshata - Kshatriya mother and Shudra father, Ayogav - Vaishya mother and Shudra father.  Further more, the child of a Mahishyo father and Karana mother is a Rathkar.  In this way are defined Sachudras and Asachudras.  Those Sachudras who are Krishna devotees, who wish for salvation, who serve the upper three castes and who obey their personal duty have the right to Diksha, Tulsi Mala and Urdvapundra

Therefore Narad Pancharatra explains, ‘Brahmins, Kshatriyas, Vaishyas and Shudras who desire salvation (Mumukshu) should wear the Tulsi Mala, Urdvapundra Tilak and the Vaishnav Mantra (Diksha Mantra).’

It was the aim of Lord Swaminarayan to return to the true Vedic teachings and therefore he taught the true Dharmas for Shudras, giving them back their rightful place in society