The Extension form (4868) is not yet ready for e-filing. It does state in the forms availability forms that right now it is available to print in the program. TurboTax Easy Tax Extension should be available in a day or so.
https://ttlc.intuit.com/community/forms/help/irs-forms-availability-table-for-turbotax-individual-pe...
https://turbotax.intuit.com/irs-tax-extensions/
