By default the TTL from the IPv4 and IPv6 headers is not propagated to the MPLS label. Propagation of TTL from the IPv4 and IPv6 headers can be configured to only propagate local packets, only propagate forwarded packets or to propagate both local and forwarded packets.
Use the mpls ip propagate-ttl command in global router or named VRF global configuration mode to configure TTL IPv4 and IPv6 header propagation to the MPLS label.
For a modification of the MPLS TTL configuration to take affect, the MPLS/LDP session must be reset. Use the no mpls ip command followed by the mpls ip command to reset the MPLS session. Use the mpls label-protocol-ldp command to re-enable the LDP session.