I've got about 110k on mine, I run Royal Purple 5w30. I used 5w20 previously but it's just too thin for summer use. Idling in traffic when it's 90* out my oil pressure would plummet towards 0 at an alarming rate. Then of course if you put a heavy summer weight oil in, once it gets cold oil pressure skyrockets and likely is bypassing the oil filter, which I don't particularly like. If you change your oil every 6 months or so it works out pretty well, 5w20 for winter use and 10w30 for summer.

 

i started using mobil 1 synthetic and my car started leaking more.

 

I figured that switching to syn. now would make my leaks worse and larger. Thats one of the reasons why i wouldnt run it. What conventional oil were you running(mtxz)?

 

5-30 syntec kn filter..i change the oil twice filter once..works fine for me

 

I use KN 3002 Filter - holds an extra 1/2 quart and i think has the anti-drainback valve. And its longer so its easier to get out or easier to reach. Three advantages over the KN 2002. Use Mobil 1, 10-30W. No leaks. I replaced all of the seals/gaskets on my 100,000 mile stock LT1 though but didn't have much of any leaks before I replaced all that.

I have always changed both filter and oil every 2000 miles or 3-4 months on whatever vehicle I own that I drive, unless it hardly gets driven(something like 200 miles in 3 months) or if it is put in winter storage.

 

Synthetic oil is great, if it leaks, fix the leak. Use NAPA Gold filters and you'll be fine.

-Dustin-