depends where the oil is coming from with your leak but you have the front and rear main seals, the oil filter adapter as you stated but there are seals for the cam and optispark and also the valve cover gaskets that leak. i prefer to use whatever GM has because i get a discount but if not them ill use fel-pro brand
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i had the passenger valve cover leaking on the rear, down the block and onto the oil pan. all thats fixed now i just have a small drip on the rear main and ill eventually fix the trans cooler lines
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i had the passenger valve cover leaking on the rear, down the block and onto the oil pan. all thats fixed now i just have a small drip on the rear main and ill eventually fix the trans cooler lines