Hey X3offroad,
Thank you for using Apple Support Communities! I understand that your message notifications are no longer appearing when connected to your Ford Sync. Getting your notifications on time is essential, and I'd love to help provide some guidance.
It's possible Do Not Disturb While Driving has been enabled, which can cause your notifications to be silenced or limited.
Check out the following support article, which provides some troubleshooting steps to try for this behavior:
Turn on Do Not Disturb While Driving on iPhone - Apple Support
Take care!