I came across an old thread on another forum where someone stated the following:

"i wouldn't put mobil 1 5W-30 in my LS1 if it was free. not after patman's analyses.

let's get something straight: mobil 1 is good oil. mobil 1 5W-30 is good oil. it's just not good for an LS1. mobil 1's 5W-30 isn't a true 30 weight, it's closer to a 20 weight. it's too thin for an LS1. that is why our LS1's tick, consume oil and sound like a sewing machine. most people use mobil 1 and it's too damn thin for the LSx line!

switch to german castrol 0W-30. it's a thicker oil and better suited for the LSx line. you'll be amazed how much quieter your engine is. it's more like a 40 weight mobil 1 oil. the only mobil 1 i'd put in my car is 0W-40 or 5W-40. i'd never use their 30 weights, they're like water.

if you have tick or that sewing machine sound, try GC 0W-30. my engine is amazingly more quiet than when i bought the car and it came with XXX oil in it. the only noise out of my engine bay is the belt noise. 2,500 miles later and it's still pretty clean too. i'm a believer.

ask patman, he'll tell you. he runs german castrol 0W-30 for 9,000 miles in his corvette and his analyses come back saying the oil could go longer. it just may be the best oil out there, especially for the LSx."

Here's the link to the thread: http://www.ls1tech.com/forums/genera...-pressure.html



Any thoughts on this? Would 5W-40 Mobil 1 possibly be better suited to the C5 than 5W-30? Or is the guy that posted this just loco?

 

Opinions about various manufacturers of oil, oil filters and oil weight are just that...opinions. GM hasn't changed the specs that I'm aware of.

Try it and report your own results. It can't hurt anything...

 

You know - it's your car, your engine, put anything in there that you want. Personally I follow the manufacturer's recommendation and use 5W30 and oil that satisfies GM4718M. Plain and simple.

No where does it mandate that you have to use Mobil 1. It is the oil that is the factory fill - but there are a number of other oils that meet GM4718M.

 

Many C5's running up to 300,000 miles without any motor problems using the original fill Mobil 1 5W30. I have always run it in my C5's and C6 and never had a motor problem. I think the 40 weight is a little thick for the stock LS1. I'm sticking with it

 

Lots of good oils out there. I continue to use Mobil 1 5W-30 because it has worked well for me.

 

amen!

 

One thing to remember, with the 5w-30w oil, the reason is the 5w allows the oil to be thin enough for cold starts, the 30w means it has the thickness of a 30w oil for protection at higher rpms it will stay between the bearings and handle the pressures of high demands. Using a 40w should be fine on older higher mileage engines. You may notice a very slight decrease in gas using the 5-40w, but nothing that will matter on a vette. As long as the oil has the required spec. that GM stated, go for it. When my vette's LS1 motor hits 300k, I'll be switching to 5-40w I'm sure...

 

 

I'ver read that conventional 10w-40 has less long term lubrication properties due to the viscosity improvers that have to be added, is that correct, and I wonder if the same would apply with synth. oil?

Anybody have any info or a link of some sort?

 

GM GM4718M (Jun 2009) lists Mobil-1 0W-20, 0W-30, 5W-30,
10W-30 for our engines

 

I really don't care what the test says, Mobil 1 is good oil (5w-30).
Do you have any idea how many LS1 motors run Mobil 1 5-30?

 

OK... I'm of a firm state of mind on this.

Those that say opinions about various motor oils are just opinions are only half right. My reasoning behind this is that oil analysis shows facts while SOTP feeling is an opinion.

Some oils may be identical in certain cases. But engine wear and tear is something you can't really feel. The debate whether or not mobil1 5w30 should be used comes up a billion times a month. Obviously there's a good amount of people that feel very strongly that you shouldn't use it. I personally don't use it. I use Amsoil. But I'm willing to spend the money for it.

When I switched my 2002 Z06 from Mobil1 to Castrol Edge I noticed the engine was quieter too. There was absolutely no difference in how the engine performed though. I've heard dozens of times about the Mobil1 weights being lower, but I've never seen proof of it.

The only thing I have to offer in my personal experiences is that switching all of my GM cars that ran Mobil1 from the factory (2 Corvettes and a Pontiac Solstice GXP) to either Castrol Edge, Penzoil Platinum and Amsoil SS made a world of difference in the sound the engine makes.

Mobil1 is the most popular factory fill oil. After reading the analysis' that are on www.bobistheoilguy.com, I've made the decision not to use Mobil1. Whether or not the analysis' on that site are correct, there's no point in risking the extra wear on my cars. I've spent a lot of money on my cars and there's no reason to cheap out on oil.

There's a lot of good oils out there. If you have doubt about Mobil1, don't use it.

 

i like Bob ...

 

Is Amsoil or Castrol the factory-fill for anything? From what I've read about the LSX engines and the C5, a whole lot of engineers spent a Long Time thinking about what kind of oil should go in a Corvette, years !

 

Amsoil is too small of a company to get factory fill status on anything, but Castrol certainly is factory fill on quite a few cars.

But just because an oil is the factory fill does not make it the best choice out there.

 

I run 15-50 mobil1 in mine. Do what you are comfortable with

 

That, or Mobil spent a lot of money and/or donated free product to be the 'factory fill' on the Corvette.

 

Not really. Sloppy motors can often use any type of oil and it'll work to spec. The difference is what people expect quality wise. Anyone who says these motors are specifically designed for Mobil1 doesn't know what they're talking about. GM put dino crude in the LS1 Trans Ams and Camaros. The only reason they put mobil1 in the Corvettes was because of the batwing oil pan. Crude oil working in LS1s... No oil-specific design there.

Exactly!

Ding! WINNER!

 

I am all for Amsoil I think it is the best hands down and I use 0w-30. But when I get my engine forged im gonna run 15w-40.

 

Mobil 1 is in the Vette at the factory because of the consideration they get from Mobil.

Similar to the campaign contributions that our legislators get.

Recently GM has even tried to get royalties on all Mobil 1 sales. They felt that they were the motivators for the sales.

I use 10W30 in my three Vettes and Viper. The oldest is a 02. It runs smooth, quiet and strong. So does the 05,08 and the 06 Viper.