Originally Posted by ResIpsa

For what it's worth, my dealer assured me that as long as I used a Stillen kit they would honor the warranty. Of course this would not cover a defect in the core or lines. I just wanted to be sure that they would not try to attribute some unrelated engine problem to the oil cooler.

It probably depends on your relationship with your dealer. At least I have some level of assurance that my warranty is safe.