Tex. Transportation Code § 501.0315

(a) The owner of a motor vehicle may designate a sole beneficiary to whom the owner's interest in the vehicle transfers on the owner's death as provided by Chapter 115, Estates Code, by submitting an application for title under Section 501.023 with the designation. To be effective, the designation must state that the transfer of an interest in the vehicle to the designated beneficiary is to occur at the transferor's death.

(b) The legal name of a beneficiary designated under this section must be included on the title.

(c) The department shall transfer title of a motor vehicle to a beneficiary designated under this section for the vehicle if the beneficiary submits:

(1) an application for title under Section 501.023 not later than the 180th day after the date of the owner's death or, if the vehicle is owned by joint owners, the last surviving owner's death, as applicable; and

(2) satisfactory proof of the death of the owner or owners, as applicable.

(d) A beneficiary designation may be changed or revoked by submitting a new application for title under Section 501.023.

(e) A beneficiary designation or a change or revocation of a beneficiary designation made on an application for title of a motor vehicle that has not been submitted to the department before the death of a vehicle's owner or owners who made, changed, or revoked the designation, as applicable, is invalid.

(f) The department may adopt rules to administer this section.