(Would any particular make/model be best for hearing?)
Time: present or near future
Place: starting in the city and driving out to the very rural country
The car is a sedan, probably with fold-down back seats (but they are not folded down at the time the character is in the trunk). Besides that it can be anything. The character is hiding, not kidnapped, and as such is not physically restricted in any way but needs to stay quiet.
Research:
I was unsurprised to find this difficult to Google. My searches were along the lines of question format, e.g. "how much hear from trunk of a car?" because in this case I couldn't think of anything better. A friend had a similar lack of success, although I don't know what her keywords were. Unfortunately I don't have a car and neither do my local friends. Facebook friends only had speculation to offer.
In responses makes/models would be helpful, but any non-speculative replies will be utterly fantastic!