There are bad credit loans that you can get to buy a car. But as a general rule this is what you can expect.
The first car loan after a severe drop in your credit score will typically be at a higher interest rate and you may be required to have a larger down payment.
Provided that you handle that first loan well, the next loan you get will be at much more favorable terms.
Because cars lose value quickly, you may not be able to refinance or trade in a vehicle until at least half of the original term has expired, for example if you have a 60 month loan, you may not be able to accomplish a trade-in until at least 30 months has passed.