I bought a new oil cooler for my 308 and there is a slight seepage of oil coming from behind the fitting. Right where the hose/flare fitting goes it. I have tried to tighten them more but that is about as tight as I feel they should be. Is there anything to stop this? It is bad but after a drive if you wipe your finger on the joint that goes into the fitting I can see a small smear of fresh oil on my finger. Any info would be appreciated. Thanks.