Red08

There was a topic on here not too long ago asking which Mobil 1 formulation to use. Last night I was watching the Introduction to Corvette DVD that came with my '08 coupe. On the section about checking the oil etc, the video showed a quart bottle of Mobil 1 Extended Performance set on top of the LS3 engine. It's my understanding that the Extended Performance formulation is supposed to be an improvement over the regular Mobil 1. At wally world, the 5 quart jug of the EP is only a couple of bucks more than the base Mobil 1.

su8pack1

I use what the manual recommends.

BSE1956

I have a cousin who is a retired chemical engineer and helped develop the first Mobil 1 formulations. Most of his explanation goes over my head but in short, the same basic multiple strings of some complex carbon molecules are in all consumer synthetics. The differences are the additives.
To gain additional performance for the Air Force, they made some other very expensive formulations that provided super low friction. In today's $$ they'd be more than $75 per quart.
Regular Mobil 1 is just fine in your engine. It will not wear out for many 1000's of miles. Just change it regularly to get the dirt out.

Gearhead Jim

IIRC, the 5W-30 Extended Performance M1 also meets the Dexos1 spec, so it would be approved for a C6. But if you stay within the OLI change limits, probably won't help much if at all.

racebum

we've had a few threads about this. M1 high mileage is the one with the best anti wear additive pack. it just so happens that those additives also shorten the life of your catalytic converter which is why api SN limits 30w to how much zinc and phosphorus it can have

turbod

Check out the Mobile One chart. Zinc and Phosphorous are the two ingrediants that differentiate the performance oil characteristics. 10W-50 for older performance engines:

http://www.mobiloil.com/USA-English/...duct_Guide.pdf

Gearhead Jim

M1 Extended Performance and M1 High Mileage, are two different oils.

IIRC, the Extended Perf meets Dexos1 but the High Mileage does not, last time I looked.

HOXXOH

Your friends in DC set those limits. When they were told what was happening to the cats by the EPA, they ruled that 80% of the safe limit would be best. Of course, they left all the engineering to accomplish it in the hands of industry. It's pretty much the same deal for mandated gas mileage.

need-for-speed

more unintended consequences

I have a question. When our "modern design" cats fail, is there an increase in back pressure or do they just do a poorer job of cleaning up emissions?

I wouldn't mind using the formulations with higher zddp.

racebum

right, i also mentioned why it does not. the higher levels of zinc and phosphorus while good for the engine shorten cat converter life. this is why 30w api SM & SN meet most manf specs but SL does not

racebum

the only somewhat cool thing about this is that machining tolerances and engine design have improved so much since the early days that we're seeing 300k miles out of engines like the LS series, hondas, ford modulars, toyotas etc. wear induced failure is rarely what kills an engine unless you drive at sustained high rpms where high anti wear levels are really needed.

having spent a good deal of time tracking various cars, especially when i was younger i would have to say that the hondas are the ones that really NEED the high zinc/phos levels. engines like the f20 have a stock redline of 9000rpm. these engines start to burn oil fairly quick if you drive them hard and use cheap oil.

i would do the same running a trackday in a c5/c6 as well. using redline for track days with its group 5 base stock which isn't breaking down even at 300deg and zinc/phos levels around 1800-2000ppm if i remember right really cuts down on engine wear. redline has about 2.5x more zinc/phos than mobil1 which is part of why it's such a good race oil.

personally i think the epa over blew the zinc/phos killing cats. many, many 90s cars have gone 200k on OE cats and 90s oil wasn't the reduced formula

Don 79 TA

unless you have seriously modified the motor or using a very aggressive ramp cam design
you'll just **** $$ away and stay awake to long at night worrying about the whole zinc related stuff

now if you have a flat tappet cam, thats different (still somewhat debatable)
but essentially a stock internal, stop worrying so much
you are not gonna degrade the motor any by using the basic M1 and proper change intervals
these motors will go a long time

but... it's your own dimes so do as you want

FWIW... i ran flat tappets with the standard M1 and never had an issue, i'll admit they weren't fast ramps or solid cams, and each motor that cam apart was spotless inside

sometimes i think the marketing these companies use make people so fearful

motors don't wear out like they did in the 50s-70s, they go way longer now-a-days

JKbride

Interesting ...any opinions on M1 0W-40?

raspyc6

question...why does penzoil say their ULTRA line is superior? Fire away.

Gearhead Jim

Because they don't work for Mobil.

hig4s

Good question, I would love to know too.. I know the older cats would just plug up. I assume new ones would be similar but not sure..

Anyone, anyone, Bueller?

Rock36

http://www.mobiloil.com/USA-English/...duct_Guide.pdf

Above is a nice Mobil oil reference link for everyone.

I personally use Mobil 1 0w40, but I'm not going to go out of my way to convince anyone else to use that. I know how these oil discussions can go

HOXXOH

Current thread on the Z06 forum. http://forums.corvetteforum.com/c6-z...h-mileage.html

I'll be using the 0W-40 + 1 qt of 0W-30 Racing instead of the 0W-30 + racing on my next change. The 0W-30 has lower ZDDP, so it's gone for me. I get in the 6000+ RPM range too often to not want the extra wear/heat protection.

need-for-speed

Thanks Don. I suspect you are correct I won't worry about the c6. I'll continue to add zddp to the Camaro since it has a flat tappet cam that does have a ramp rate that is > stock

need-for-speed

Exactly. Back in the day, they would plug up. That's why we had to remove them