Air filters, oil and engine wear results

[uzz32pete]

Hi Guys,
I pretty much run a quality 10W mineral oil in my 1UZ-FE V8 nowadays with excessive changes at 5000km or 3000 miles. For special events I'll run a 0W full synthetic motor oil (events like a dyno day or a weekend of 220 kph circuit sprinting)
Without a doubt quality oil will "last" longer than 5000 km without breaking down.
Topping up the oil will also make it "last" much longer as well. I never lose enough in 5000 km to warrant topping up at all.
I guess I change the oil so often because it makes me feel good! Like washing the car I like to keep the engine clean and slowly make it cleaner. Even though the oil doesn't break down, it does get contaminated with fuel and other combustion by products and the filter does block up.
I like to run the standard PCV (replaced the valve with a new one ) system so that the inside of the engine gets nice fresh filtered air and acidic conaminants are removed. I haven't had a problem with detonation.
I have travelled approx 90 000 km (56 000 miles) with this engine and the wear metals in the oil are satisfactory each oil change.

I am unable to judge oils by inspection during a service or by colour on the dipstick! Superpowers like that would save me lab analysis money!

So it would seem after several analyses that for a short 5000 km interval there is no difference in engine protection between a full synthetic oil and a mineral oil.
There is plenty of evidence that a full synthetic oil has better lube properties and is the only way to go for an extended service period. But for a 5000 km change the lab couldn't measure any superior properties.

The lab analysis is also handy for finding out what is in oil and how different companies approach their formulaes. Check out the levels of moly added to oils for example -some are low and some are high (link at bottom of page).

It would also appear that a TRD oiled cotton air filter is satisfactory for filtering air. The engine oil is exposed to dirt in the intake air through the pcv system and as a part of the combustion process. An oil analysis will clearly show if there are leaks in the air intake system and the levels of dirt contamination in the engine oil and and correspoding increase in wear metals.

There is some more information on this page including the oil analysis results.
http://www.planetsoarer.com/OilAnalysis/OilAnalysis.htm

best regards
Peter Scott

 

[Cobber]

Moly in an engine oil? Mad. Hammer oil maybe.
I can't see anywhere in the Toyota oil specs asking for solid additives such as moly.

Oil anaylisis should be used as a trending tool and to look at results as an absolute figure can be destorted by other factors. New engines will often have massive wear metal results, does this mean the engine is stuffed or the oil is no good, no.

As Peter says below for such short oil change intervals a mineral oil will surfice.
Pick one with the latest SJ rating and a viscosity that suits your ambient temperatures.

High temperature, high horsepower, extended oil drains use a true synthetic.
By this I mean a group 4 synthasized hydrocarbon, not a group 3 hydrofinished de waxed mineral. Mineral oils can legaly be sold as synthetics, buyer beware.

Polyphaolefin based synthetics derived from ethylene gas such as Mobil 1 also have esters added to aid in additive solubility. The esters will have a cleansing effect and can affect the wear metal trends on initial conversion. It can also clean out the carbon deposits in older engines which sometimes is the only thing holding them together.

Dirt will show up generaly as a mixture of Silicon & Aluminium at a ratio of 4 - 1. As silicon is not trended the Aluminium spikes could well represent dirt ingress and not wear metals.

Pick an engine oil that suits you and your driving conditions.

Trust me I'm a Tribologist.

 

[SCV8]

That's good info, now I can rest easy about using a K&N on a car that I never want to have to do a valve job on.
I agree about the PCV, they're a good thing.

 

[cribbj]

Hurray, we've got a real tribologist here!

Cobber, let's get some discussion started about, oils, lubricants and filters for these engines, trannies and diffs. This is one of those mystical, cult areas where innocent people get sucked in by marketing hype (anyone remember Slick 50?), and the real experts remain silent.

In your opinion, what's the best oil to run in our high performance motors with reasonable oil changes? 5w-15, 10W-30? Mobil1, Castrol, synthetic, nonsynthetic, etc.?

Does Redline have any advantages at all over Mobil1, besides better marketing?

Is there anything inherently better about Amsoil's products, or are they just the Amway of lubricants?

Are Toyota filters really lightyears ahead of the pack?

Inquiring minds want to know......:veryhappy

 

[Cobber]

Oil is such an emotional subjet because it is a "performance product" picked off the shelf.

I will just say that for my application (standard 1uz with m90 @ 8 psi) I will be running Mobil 1 0W-40 with 10,000 km oil changes.

I will put together a fact sheet to help people better understand specifications of oils. The choice is upto the end user.

For eg

0w only relates to the cold cranking capability and will not give you extra power at running temperature.

The second number 30 or 40 etc gives you the oils viscosity @ 100 deg c (running temp).

Magnetic oils?

zinc dithiophosphate bonds to the surfaces.

Engine oils from the 30's have had this technology.