What kind of tricks do you guys have for the 4.0L valve cover leaks? We're not talking a small leak either, this it the big one that makes the smoke screen behind the vehicle. It's a 94 grand cherokee with an aluminum cover. I've used the right stuff a couple of times and it always seems to leak on the intake side. Does anyone make a rubber one for it? I've searched and couldn't find anything. Thanks in advance.