$str = '175/60 R15';
preg_match('!^([0-9]+)\/([0-9]+)\s(.*?)$!siu', $str,$res);
print_r($res);
$str='5,5 x 15 ET45';
preg_match('!^([0-9,.]+)\sx\s([0-9,.]+)\s(.*?)$!siu', $str,$res);
print_r($res);
$str = '175/60 R15';
$str2='5,5 x 15 ET45';
function myfunct($sym = [],$str = ''){
$editString = str_replace($sym, $sym[0],$str);
$result = explode($sym[0],$editString);
return $result;
}
$result2 = myfunct(array("/"," "),$str);
$result3 = myfunct(array("x ", " ET"),$str2);
var_dump($result2);
var_dump($result3);