Oil question
Thread Starter
Instructor
Joined: Oct 2006
Posts: 240
Likes: 0
From: Richmond VA
Oil question
in the manual it says that 5-30 is recommended. My dads shop only had 5-40 mobil 1 synthetic so I went with that.
Whats the difference between the two and is going to hurt my motor?
Whats the difference between the two and is going to hurt my motor?
Le Mans Master
Joined: Feb 2002
Posts: 6,937
Likes: 21
From: Waldorf MD
The LS1 is a low clearance engine, I would not run 5W-40 in it. Will it hurt your engine, no, I doubt that. Your HP and gas mileage will be a little down. I would get it out before any cold weather though.
I wouldn't go as far as panicking. But I would change it out just for peace of mind. David 
Race Director
Joined: Dec 2000
Posts: 19,304
Likes: 85
From: San Diego CA
Are you sure it's not 0W-40 synthetic Mobil 1? I don't think that a 5W-40 would cause any harm since it's the 5W designation that is most important. 0W-30 or 0W-40 and 5W-30 are more common synthetic oils, but as long as your oil is made by a well-known oil company and it is approved for use in the C5, keep it in.
