I find a contentment in an older car that can never be matched by a new car. It’s the contentment you get not worrying about the next ding from a near by door in a parking lot. I feel others feel the same way.
Your older car is worth keeping if for piece of mind alone.
We have this discussion at my house regularly. My wife drives a 12 year old car that she likes. I have been after her for some time that we need to make plans to replace it. She just asks how long I can keep it running reliably.
I, on the other hand, have been driving the same car for almost 4 years and I’m about done with it. It’s time for something different. Since we can’t afford 2 car payments we need to plan car purchases. I’ve told her that if she doesn’t get something soon, I’m going to buy one. Then she complains that this will be my fourth car purchase since her one 12 years ago, and she should be the next one to get a car.
I can’t win…
That’s right @asemaster. You can’t win this one. Get your car cleaned up and detailed and it’ll feel new enough to keep, then start taking her shopping for a car for her.
I should’ve mentioned this earlier, I live in India, which means bad, bad roads, the kind most of you can’t even imagine
You still think that under these conditions my car is not old and will last another 10-12 years?
Yes, Champak, it still applies. The economics just don’t work - except for the body work issue.
That does change things. I would have a good mechanic go over the car to see what might need to be fixed. If it is in good shape I’d still keep driving it.
Financially it’s best to get rid of a vehicle when there is no resale value. If you want to sell it when resale value is high…then buy new every year.
If the vehicle is running good…then keep it. Far cheaper to keep a decent car running longer then buying (or especially leasing) new all the time.
Thank you for the added information
I will now advise you to service the car, as per the EXTREME maintenance schedule
I will probably drive my current purchased new in 2010 car for 10 years but I might get a toy to relieve the boredom. I might get another Miata I loved my 1996. More fun than my old British roadsters without the pain.
Short of the 1.5 foot deep standing water, I thought he was talking about Oklahoma for a moment… 
What I would suggest inspecting closely and keeping an eye on are brake and suspension components; especially ball joints.
@chmpak In India labor is very cheap, and I am told cars like your Ambassador live virtually forever, being rebuilt constantly. If you use your car for business, you may need it to be available nearly all the time, so having it in the shop frequently may not be desirable.
However, a good car in India should last you at least 15 years without being unreliable.
Replace it when you want to get a different car or when it no no longer provides the quality you want.
Replacing it sooner will cost you more, but it also may give you more fun or convenient features or functions. In the end you need to make up your mind. I generally keep mine a long time I have never had a car fail me.
For example I got a new car after a grey hound bus hit me on the freeway.
For most people keeping your car as long as possible is the cheapest, but if you want something newer or fancier and you can afford it, a new car.
Keeping it usually is the cheapest.