<?php

$cars = array_map(function ($id) {
	return [
		'ID' => $id,
		'title' => 'FooBar'.$id
	];
}, [1, 2, 2, 3, 5]);

$cars = array_values(array_reduce($cars, function ($result, $item) {
    $result[$item['ID']] = $item;
    return $result;
}, []));

var_dump($cars);