Hi,
There is no technical difference between them.
The TJA1044T,118 (12NC: 935297572118) is a dual source type meaning diffusion is performed by ICN8 Nijmegen or SSMC Singapore and assembly/test is done done at the NXP Bangkok Thailand facility.
The TJA1044T/1Z (12NC: 935307168431) is a quad source type meaning diffusion is performed by ICN8 Nijmegen or SSMC Singapore and assembly/test can be done either at the NXP Bangkok Thailand facility or at ASE Suzhou China.
If you need a detailed information about the marking for both the TJA1044T,118 and TJA1044T/1Z, please create a standard ticket/case.
Best regards,
Tomas