James2002z06

But I do not run any thing synthetic ....

olbear1962

Switched to Amsoil 5W30 signature series, full synthetic.

VETJAZZ

I use whatever's on sale. Usually Mobil 1 or Pennzoil Platinum.

Vetteman Jack

I use the fully synthetic Mobil 1 5W30 - has always worked well for me.

striper

I use Pennzoil Ultra or Castrol Edge, along with a NAPA Gold filter (another subject). I figure if Ultra is good enough for Ferrari's factory fill, it should be good enough for me. Wally's was out of Pennzoil so I picked up the Castrol. I've read too many reports on the current state of Mobil 1, so I haven't used it in quite a long time. At this point in my car's life, we are now at 117k miles and it still doesn't use a drop between oil changes, which I do approximately whenever the DIC says 50% usage ( and that's another topic).

jdot

When I was a young man (long ago) and had just gotten my first car; a 57 Buick Special, my cousin who was a very fine mechanic told me "as long as it shows level on the dipstick the oil is the same." I still use Mobil 1 in my Vette.

GCG

C66 Racing

Stepping into the minefield, but some may get something out of this:
AMSOIL Performance Test: A Study of SAE 5w30 Synthetic Motor Oil

The AMSOIL test includes most (not all) of the oil's mentioned in this thread. Even if you discount the AMSOIL results, you can get a good feel for how the various other options perform.

More than happy to get AMSOIL products for forum members at dealer wholesale pricing, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested.

rws.1

There are really only 3 things your need to know to buy oil for your Vette
1. Does it meet the manufacturer's spec (GM4718M for the C5)?
2. Is it good for where/how I drive my car( regular/severe service, hot, cold climate)?
3. Is it a brand I know and trust?


I use Pennzoil Platinum or Quaker State Ultimate Durability in our Vettes.

rws.1

????
there is NO non-synthetic motor oil to my knowledge that meets GM4718M

Exactly what oil are you using?

Mr.Bill

Not a one and know a lot of others that use RP without issues.

01vette360

What is any other oil gonna give you Mobil1 does not provide? Please back your response up with facts not IMO or its seems to....

I really wanna know???

memmer

Most of the oils mentioned here will work fine.Oil does NOT wear out, only the additives get used up. Oil will collect moisture and impurities over time thus the need for a oil change.I run with Mobil 1
Fred

striper

I'm no oil expert by any means, so i can only tell about what I have read posted here. According to publications from within the oil industry posted here, it is the additives that Mobil 1 uses that are supposedly not up to quality they originally used. The issue was that they breakdown sooner than most, especially the 5W as opposed to the 10W. It was recommended that if you use Mobil 1 you should at least use their 10W-30 instead of the 5W-30. Just sayin.' It's easy enough to buy another brand at similar prices that have better current reputations such as Pennzoil. Though it is not relevant anymore with synthetics, years ago I started using Pennzoil and Quaker State because Pennsylvania crude made better base stocks than other parts of the earth. Partly for that reason and never having a problem with them, I've stuck with those brands all these years. BTW, I've also used Royal Purple without any problems, other than it's significantly more expensive than the other brands. I use RP for trans and diff fills.

OneCylinder

Oil lubricates and cleans the cylinder walls carrying away the combustion residuals. So while it may not wear out, it does get dirty. That's why oil turns dark soon after it has been changed.

OneCylinder

Federal regulations required that the ZDDP (wear protection components) be reduced by about a third from all non-racing, non diesel oils. The issue is finding a 5-30w with a higher ZDDP content. Our engines were designed to use the old Mobil 1 with the higher ZDDP content. This may be a bigger issue on engines with higher lift and duration cams than stock. Joe Gibbs has a 5-30 designed for such applications and claims to have a higher ZDDP level than other 5-30s.

James2002z06

In my motor is the the block .....

James2002z06

C66 Racing

Fred,
I think that is overly simplistic. The basestock in oil can thicken due to high volatility (e.g. as the fluid evaporates, it thickens). It can also drop over time due to viscosity shear down (e.g. the molecules in the basestock actually break and become smaller molecules lowering viscosity). And the viscosity improvers can break as well which will turn a 5w30 into a 5w25 then 5w20 etc. Most of this is very dependent on the basestock and the operating conditions and in general, doesn't happen to any major extent in daily driven cars. But if you look at enough used oil analysis reports on the oil forums, I think these sort of problems do crop up. My thoughts only - not meant to start a debate.

Bullet Proof

I'd bet most synthetic oils will outlast the filter media.....that's the weak link.