I used to use 10W30 Oil most of the year and 5W30 in the cold winter months. That was with my old stock motor and we pulled it out at 120K and it was in great shape. With my new 383 motor and the different clearances for a supercharger set up, the engine builder told me to stick with 10W30 Year round and thats what I have been doing and its worked great so far (appx 17K miles).

Thx,
Claude

 

I posted this one one other one.

I run 4 quarts 5-30 and 1 quart Lucas oil. I seriously recomend this for engines with over a 100,000 miles. It's better than just putting in 10W-30, because it sticks to parts and doesn't just run off, which means no more "Hard Start ups" Plus it reduces blow-by. So you will get a little less carbon and stuff on your tips.

Try it you'll never go back

Jason

"White Knight"

 

I've used Mobil 1 Tri-Synthetic 10W 30 in fall and winter for years with no ill affect from inclement northeast weather.

Presently running Castrol Syntec 0W 30 (Germany) all year round.

 

I just changed the oil in my 94Z28 for the first time (bought it a couple of weeks ago) and used Mobil 1 10W-30. You can't go wrong with it.

 

10w 40 synthetic blend. works good for me in CA especially after this pretty hot summer we had

 

I use 15W30... hmm wonder if i should go to 10W30... so far it seems good.. read that it has a higher heat rating as well(15W30)