ok so i drove my truck out of town today and it started knocking so i pull over and call AAA i need to know what can it be. it has a new head on it. the knocking is only at high rpm's sometimes it will sound fine and sometimes it knocks but when it knocks it is loud. there is no oil in the water and no water in the oil. i pulled the moter and really dont whant to take off the oil pan dew to my finding i need a full rebuild kit.right now the motor is at my house and my truck is at my friends dads house 250 mile away. if you have any clue please let me know thank you..