I'm using Mobil 1 which I was told to do, and this has always been used in the car. Is there a better choice?

 

you will get alot of varying opinions on this subject, and the archives are full of discussions about engine oil.

The Engineers that designed the engine specified Mobil 1.

You can always spend more for a different brand, but a stock LS engine will go 200-300 K miles or more with Mobil 1.

Let the discussion begin

 

Oh hell. Not my intension to stir the pot. The motor is not entirely stock and I can get into more details about that if needed.

 

i'm not sure it really matters in street driving

in a racing environment high additive high zddp oils are useful but that's a lot more heat and a lot more stress

a friend of mine tore down a honda with 320k he bought new and always fed mobil 1 the other day. head gasket went. anyway, bearings looked great in the bottom end, bores were in good shape and there was very little guide wear. there was some oil burning due to rings which were replaced with a hone but no sludge at all and clean looking aluminum in the engine

320k miles. street car, never raced etc

 

Everyone has an opinion, here's mine

Mine is not stock either. EPA has been reducing ZDDP levels in newer oils, so Mobil-1 5W-30 is not the same oil that existed when these cars were built. I am now running Amsoil Z-Rod oil in the car to keep the ZDDP and phosphorous additives to a level that will protect the higher loads in my valve train. I have seen several cars with worn pushrod ends and other failures that to me look to be oil related. I am trying not to join that group.

 

Mobil 0w-40. Many good reviews

 

IMO its just business. Mobil was low bidder to supply GM with oil.

 

Although this is

GM recommended oil meeting the GM4718M specification.

They also state that the factory fill is Mobil 1, although they do not specifically recommend it.

Therefore any oil meeting the specification is what they recommended and Mobil 1 is one of those oils. There are many others that meet the spec. also. There are also many synthetic oils that do not meet the specification.

The labeling to state it meets GM4718M required that it be submitted for testing to that specification. There was a cost involved to have it certified, so not all oils were submitted and therefore not labeled as meeting the spec even if they might have passed the testing.

The GM4718M specification has been superceded by the Dexos certifications. They specifications are not the same, however I don't know if an oil passes the Dexos certification if it would also pass the GM4718M spec. Several oils list the Dexos specification but not the GM4718M spec.

In practice, Mobil 1 (and other oils) have changed since our cars were built. I suspect that any of the major brand synthetics would not cause a problem, but if you are trying to follow GM recommendations that came with our cars then find one listing GM4718M in the right viscosity.

 

Without trying to start another oil debate, you might find this interesting even if you discount AMSOIL from the results:
AMSOIL Performance Test: A Study of SAE 5w30 Synthetic Motor Oil

 

I've been thinking about switching from mobil 1 to Amsoil... What stores usually carry amsoil?

 

So many discussions on oil over the years

Mobil 1 is the factory fill. It is readily available at Walmart, Target, Costco, auto parts stores. I've used Mobil 1 in all my cars since 1985 without issue

 

I was thinking of trying the Signature Series 5W-30 since it is rated as GM dexos1 (supersedes GM 4718M). It sure tests well against the competition per your linked test report.

What's the best way to purchase Amsoil at best possible price. Amsoil's website says this is about $10 per quart.

 

The on line store

 

Or do a Google search for Amsoil dealers near your location. Found one close to me, so easier than ordering on-line.

 

Not many stores carry AMSOIL as their corporate approach is a "mom and pop" philosophy. They prohibit accounts being set up with corporate chains (e.g. will never be at Walmart) or with chains with more than 12 stores. Independently franchised stores (like most Napa stores) can set up accounts - I have many accounts with local stores.

Easiest, most cost effective way to get AMSOIL is through me. Drop me a PM with what you'd like and your zip or city/state and I'll let you know the cost to have it shipped to you door. Sell it this way to hundreds of forum members.

 

I was in Autozone today and noticed they have the Castrol 0w30 european blend. I know alot of the LS1 guys use this, I assume alot of ppl with LS6 cars do too? I looked on the back of the bottle and it said made in Germany so I assume thats the good stuff.

 

Somewhat dated now as this was done in 2005, but the oil specs haven't changed much since then. With the help of a fellow forum member, we compared AMSOIL's top tier Series 2000 0w30 (now branded Signature Series vice Series 2000) vs. German Castrol 0w30. Both showed very low wear metals in used oil analysis.
Used Oil Analysis Comparison: German Castrol 0w30 vs AMSOIL Series 2000 0w30

 

Thank you sir

 

 

Am running Amsoil Signature series, 5W30. I have a stock engine, and don't track or race.
Did the endless reading of threads and posts........absolutely endless.

I settled on Amsoil out of personal preference, many good oils out there, can get confusing.

Good luck with your search.