RC81

I know 5w/30 flows better than 10w/30 but is it to thin to provide proper protection? Talking about a synthetic for myself but probably applies to regular oil as well. Is thiner or thicker better in a newer motor?

69er

10w40 Amsoil.
Not too light-Not too heavy.
:cheers:

Tele_Man

10W40 in the winter and 20W50 in the summer. I'm running a 427 BB and it gets pretty hot in the summer.

JBR

15w40 Pennsoil diesel. From what I read it counter acts some of the bad additives in the s**t gas made today. :cheers:

Jvette73

Mobil1 synth 10w-30 year round. Great stuff and highly available. Its in all my cars. Newer and older.

427V8

10w30 Amzoil.

Keeps the oil pressure in tolerance.

Ryan77

I run Valvoline 10W-30 in my truck and will be running Mobil 1 10W-30 in my new motor for the vette :cheers:

Wrencher

Straight 40W Redline. Never gets cold here and cuts down on foaming.

Hans

BlueL36

10w30. Just what the General says to use.

Wrecked82

10W40 Delo 400 (Chevron diesel)

Twin_Turbo

This stuff

tomservo291

ams oil all the way, never trusted anything else in the '79 camaro with a 350 pushing 450hp normally aspirated; performed like a champ day in and out.

OHSIXX

Changing to Mobil 1 Syn as soon as engine has 5K on it. I have always used 10W30. Sorta a middle ground.

Motor City Vette

Valvoline 10w30 Max LIfe

Corvette_fetish

Royal Purple 50W synthetic
My motor is old, worn out and burning a lot of oil. Royal Purple add a few horsepower and protects very well extending what's left of this engine's life. My mechanic claims the Royal Purple behaves like a thinner oil, so the R.P. 50W is not as thick as it sounds. All I know is when I put 10W30 conventional in it just after I got it, it burned through it a lot quicker and I almost accidentally ceased up the motor as a result.

Tominator

Quaker State 10/40, I orginally ran 20/50 in it after the rebuild but the oil pressure was maxed out most of the time. Switched to Mobil One but engine started leaking. Switched back to Quaker State (QS) and it doesn't leak much now.

The reason for QS is many moons ago I had a Chevy Chevette 4 door (the kind that girls dig :D) and always ran the cheapest oil I could find for it. Anyways the engine would knock not to long after an oil change. My dad told me I should use better oils and it would make a differnce.

My findings were this (roughtly) Castol would get close to 2000 miles (after oil change) before it would knock, Pennsoil over 2500 and Quaker State would go over 3000 miles.

pws69

Mobil 1 - 15W50.

I only drive it in the summer.

ettev

20W-50 Castrol GTX & an AC Delco filter. Change both once a year (only put about 500 miles per year TOPS on it).

Wrecked82

Failed to mention, engine has roughly 125K HARD! miles on it. Does not use ANY oil. And, oil is same color as it went in when it comes out 5K miles later.

Sold on diesel oil.

red79c3

valvoline 10/30 and why not???