I have a pretty good il leak on my LT1 ... I have an oil cooler that was recently put on ... the cause of my leaks ... It consists of a adapter, which has two lines going in and out of it. One to feed the cooler and one to return the oil ... This adapter goes on where the factory oil cooler ( The retarded one that works off of antifreeze ... ) adapter was. Then the filter screws onto the bottom of that. I put the adapter in, threaded the line adapters into it, and put the filter on, hooked it all up, and when i filled the car with fresh oil , it leaks ... At first I thought it was the hoses leaking once the oil pump builds up pressure ( Engine doesnt run yet as i need new injectors and am waiting for them ... ) so i tightened the brass fittings even more that screw into the adapter, and i tightened up my hose clamps that clamp the hose to the brass fitting. Wait till the next day ( CAR DOESNT RUN ... ) Oil everywhere again ... so i whipe it off , take the filter off , and tighten the adapter. Still leaks ... I donno what to try now ... The oil is from above the filter , so its not the filter leaking. And i felt the TOP of the adapter and theres no oil on the top ring where it meets the block ... Yet if i reah about a half an inch lower, there is a little ledge, and that ledge is covered in oil, it then rolls off there and down on the filter and under my car ... its a pretty good leak seeings how nuthing has been under any more pressure then cranking the engine ... How could Oil be on top of the ledge, where there is no seals, but no oil where it meets the block ... Is it possible that the back of the intake is leaking ? I hear this pretty common on LT1's ... yet my engine has only 13,000 Miles , original engine, and the intake manifold was never off ...

 

Frankly, I'd get rid of the oil cooler. Unless you are running circle track, you probably don't need it. I'd just go with Mobil 1 5W30 with a good filter and sell the cooler to someone else.

 

I might do that lol ... I do use Mobil 1 ...