It doesn't sound like any 'alarm' signal associated with the vehicle. If it has done it only once I wouldn't worry about it unless it repeats itself. Are you certain that it wasn't a noise which came from something else electronic in the car (i.e.; your cellphone, or similar item for instance)? If it repeats itself, call a Tyoota dealer's service department and ask.
30mph
Yes you can, only to 4x4 high it must also be below 30mph
when a car is speeding up how does the forward force and air resistance compare
The ability of a car to climb a certain grade slope at a certain speed is it's gradeability. My Toyota Echo could take a 45% slope @30mph. (Its gradeability)
30mph
30mph
30mph
48.28032 kph ==
i think 30mph
30mph
they can run 30mph
around 30mph