Magnatec 10W-40 vs Edge FST 10W-60... with real data

[Boof777]

Hi all, little bit of background info to start;

So I recently bought a used 2007 VE Calais V in Evoke with black leather along with the L98/6L80E/2.92 Non-LSD driveline combination. Love the car and is in great condition with 118,oookm [now 13o,oookm]. Was 1 private owner from new with full Holden service history and no modifications.

Sorted out a few things like the harmonic balancer which I replaced with a Powerbond item from MACE [great company to deal with and no one came close to their price], new spark plugs, drive belts [PK1090 for the Aircon as I need to get the upgraded bracket], transmission fluid checked and coolant flushed and replaced. Still have a few things left to do but it’s getting there.

Now, what I wasn’t impressed with was the factory 15,oookm engine oil change intervals. Even with a 8+ liter fluid capacity. Not to mention the Holden dealerships used Castrol Magnatec in a 5W-30 for this vehicle and that oil, IMHO, should not be left in that long being a semi synthetic [at best] and the fact the car is from, and will continue to be, in Queensland. Also the fact it’s so thin at operating temp, the HTHS must be pretty low. I immediately changed the oil to Magnatec 10W-40 for the interim.

I am planning to keep the vehicle for a long time so I went looking here and other forums for a good oil that I can run which would meet the following criteria;

- reasonably priced
- easily attainable at major retailers
- will go 8-1o,oookm before replacement is needed [group4/5 synthetic most likely]
- will give me good protection [high HTHS]

Seems a lot of people like the Castrol Edge Sport 10W-60 [obsolete] and the newer FST labelled oil seems to be just as good and with the API SN certification. From what I could find, it’s also a group4/5 full synthetic base stock as opposed to a lot of other ‘Full Synthetics’ getting around with majority group 3 base stock and 20-30% group 4/5 added.

They were also a fair few people who advised against using it. Nosy valvetrains, too thick [maybe the most common statement], not manufacturer spec, your engine will implode and create a black hole which will result in the end of existence etc, etc, etc…

So I decided to test some differences with the Magnatec 10W-40 and Edge FST 10W-60. Some of my test parameters/conditions;

- Both oils have covered approx. 75okm
- Filters changed and oil flushed with each oil change
- Ambient temp was within 5deg C
- Same driving conditions

Basically, I have tried to keep things uniform so that I can get some accurate figures for those interested in how the oils perform inside your engine without a bias.

***The internal condition of my engine may or may not be different to others. All I can say is that it's a stock engine and has never been opened as far as I'm aware.***

As you can see from the attachments, there isn’t a great deal of difference with the 10W-60 compared to the 10W-40 oil. Oil pressure is obviously up, but it’s not as much as you’d think. Gives me an extra 5psi @ 4oooRPM along with 5-6psi @ hot idle, not to mention the extra protection with a HTHS of 5.1 and being a full synthetic, I should get my 8-1o,oookm service interval [with my 50.50 highway/urban driving].

Anyway, have a look at the attachments for the figures I obtained. If you want good protection for your engine, the Castrol Edge FST 10W-60 gets my vote. IMHO, thin oils such as 0W-20, 5W-30 are a compromise, they don’t offer the same level of protection as a 40, 50 or 60 multi grade engine oil. A lot of high end Euro manufacturer’s used to recommend the 10W-60 oil for their performance models too…

[/IMG]
Conditions from LEFT to RIGHT of image as follows;
- Cold [Ambient] Start-up Idle
- 2oooRPM
- 3oooRPM
- 4oooRPM
- Hot Idle

Magnatec 10W-40

Edge FST 10W-60

 

[Benboy]

I'd suggest you stick with what Holden Engineers have recommended (specifics usually found in the Owners Handbook). As for oil and filter change, I have always changed every 5,000 km (oil AND filter). If you chose 7,500 km your engine would absolutely love you.

 

[greenacc]

Doesnt the handbook provide a range of acceptable oil grades depending on temperature and driving conditions?
Why stick to the Holden spec for the oil grade but not the service interval...

 

[Tonner Matt]

The old debate "Is Castrol 10w60 better than xx/xx weight oil" has definitely been debated/argued about plenty of times before now.
I only want to add a Basic Hydraulic principle:
Pressure is created by resistance to flow

 

[Boof777]

The old debate "Is Castrol 10w60 better than xx/xx weight oil" has definitely been debated/argued about plenty of times before now.
I only want to add a Basic Hydraulic principle:
Pressure is created by resistance to flow

Yep agree 100%.

A fast flowing oil might have lower oil pressure, but can have better cooling and minimal wear as well.

Gas turbine engines in particular use an oil which is 5cst @ 100deg C. Fast flow, usually running around 40-90psi oil pressure, great thermal properties, temps around 60-85degC during operation. Albeit there's some extra cooling for the oil.

On the other hand, too low a flow rate will create high pressures, but can also have less cooling ability and possibly more wear.

I was just trying to show that the Edge 10W-60 in particular, still flows really well in practice in my L98 compared to the 10W-40. Especially considering the Edge 10W-60 is 24cst @ 100degC compared to 14.5cst @ 100deg C of the Magnatec 10W-40 on paper. Much more resistance to flow.

As such, I expected a much higher oil pressure reading which would be the deciding factor for me. With barely a 5psi increase in pressure at 4oooRPM, I think i will at least run it for this OCI and see how things go.

Depends on the engine type and internal clearances, galleries etc. The GM 6.0lt is no high tech engine, which is why I love them.

 

[Tonner Matt]

Why stick to the Holden spec for the oil grade but not the service interval...

Because the recommended oil change schedule is just f@#king ridiculous at every 15,000km's.
I'm not trying to belittle anyone, but the average person doesn't realize just how contaminated the engine oil can get in their car.
I change my oil & filter every 5,000km's even though the service interval is every 10,000km's, and so do many other people.
At the end of the day it's up to the individual whether they do their oil & filter changes more regularly, or stick to the manufacturers service schedule.

 

[greenacc]

And I agree 15000 k changes are crazy and designed to give short term cost savings but blow up your engine long before its time so you go and buy another car from them.
My point is don't be fooled into thinking Holdens spec for oil weight is gospel either. If they are specifying 15000k changes then you have to question everything else as well.
I change my oil about every 8000 Ks and keep an eye on its colour in the meantime.

 

[EYY]

That's right, a thicker oil won't move through the engine (and oil galleries) as quickly - so the increased oil pressure may not be all that relevant. It doesn't necessarily mean that the bearings are seeing that increased pressure/flow.

Obviously this will differ for different engines.

 

[Boof777]

I am planning on getting UOA done at 5,oookm to see how things are going with the Edge 10W-60. Have an interstate trip coming up so shouldn't take too long to rack up those kms.

Will of course post those results here.