I'm still driving the same car I drove as a CFI, regional co-pilot, captain, and now major FO (20+ years old). I flew with a CA who still drives his 1992 Ford Explorer and he's been at a legacy for over 30 years.

Buying new cars is the fastest way to the poor house especially as a low income individual.

That being said, keep your car. Treat it like it's your last. When the value hits $5k drop comp and collision on your insurance. Liability on mine comes to around $20/month. If you want a great financial tip, set your life up to live like a regional FO and save/invest the rest. Don't let the pay cut to a major deter you like most guys who go through life and buy their 'captain' toys (new car, boat, expensive house, etc.).