Thread: Oils - can we set up a definitive list

Originally Posted by rick130

What I was warned with that though is that you are depleting the add pack and so increasing wear.

What soot condemnation limits were they using Ben ?

I never had any measurable increase in viscosity with the Patrol from soot, even back in the 500ppm sulphur days, although Terry Dyson who did my analysis wasn't happy with the absolute soot levels @ 10 and 15,000km with the Tdi, reckoning they were too high for the milage and hence making an impact on wear.

The study reported no measurale adverse effects after 12 years on canola based FAME. Some engines from the diesel and RME groups were pulled down and inspected for wear with no significant differences.

Oil change intervals appear not to be based on soot. The study states that oil change intervals were 7500/10000 km for IDI light passenger/light utility vehicles, 20000 km for commonrail vehicles, and it seems 20000 km typically for HVs. (though they must have let some go to 35000-38000 km as that is how high the graphs go. Average soot content when oil was analysed varies between 0.3 and 2%.

On your soot, it is irrefutable that soot increases viscosity, as has been proven in our own and other studies which have added soot to clean engine oil. However, this can be offset by issues like fuel dilution (in the BD case), and viscosity decrease in the oil during use/aging - however this is supposed to be rare. We have "artificially aged" RX Super in the lab (without adding soot) and had the viscosity decrease. This is reported to be due to breakdown in the some of the components/additives in the oil.

Multigrade oils will shear, it all depends on the viscosity of the base oils and type and quality of the viscosity index improver's used.

As an example, older M1 0W-40 was known to sometimes shear to an xW-30 in 'normal' use in car engines.

Thickening from soot is also an oxidation process, so TBN, base oils and the entire additive package also play a huge role in how quickly an oil will thicken.
It's why the premium syn oils can go over 100,000km in truck engines yet the premium mineral based brews like RX Super are maxed out at around 30,000km.

I was using a 5W-40 oil at the time and would have to try and dig up the old tests to see what it ended up.

Originally Posted by rick130

Multigrade oils will shear...

...


Thickening from soot is also an oxidation process, so TBN, base oils and the entire additive package also play a huge role in how quickly an oil will thicken.....

I am talking about pure mechanical properties, i.e. oils that have never been subjected to shear forces. So the influence of soot and/or (thermal/oxidative) aging can be examined in isolation from other effects.

So again - in the absence of any thermal, shear or oxidative effects, soot increases oil viscosity. I will scan the graphs when I have a moment and post them.

So again - in the absence of any thermal, shear or oxidative effects, soot increases oil viscosity.

I'm sort of a bit surprised that no one's ever 'proved' that before, I've always taken it as a given ?

Originally Posted by rick130

I'm sort of a bit surprised that no one's ever 'proved' that before, I've always taken it as a given ?

Nothing especially groundbreaking, no, however the rate of increase is important - it is usually not linear.

Hi all, just after a bit of oil advice.

I have been trying to get some Delvac from my fuel/oil supplier that we use for the farm, but he has delivered Mobil Formula S2 10w40 instead. After checking on Mobil's site, this is a semi-synth A3/B3 oil with the following blurb -
Mobil Formula S2 10W-40 is suitable for use in gasoline, LPG and light to medium diesel powered vehicles. It is ideally suited for normal to occasionally severe operating conditions, highway cruising and some high performance applications.

Is this ok for a D2 TD5 (maybe shorter oils changes) or should I go for the "proper" Delvac?

Cheers,
Nova

Penrite have consolidated and changed the names for some of their HD diesel oils and gear/trans/manual trans lubes.

Penrite Diesel SP 10W-40 has now become Enviro + 10W-40 and SIN Diesel has disappeared.
Enviro Plus is an ACEA E4/E6/E9 spec oil, with various manufacturer approvals. (not just 'meets' a spec but has been tested and approved by the engine builder) and is very good heavy duty diesel engine oil.

cut and paste from their site
Trans Gear 75W-80 replaces Manual Gear Oil 75
Trans Gear 75W-90 replaces Transaxle 75, Transaxle 80 and Manual Gear Oil 80

Pro Gear 70W-75 replaces Manual Gear Oil 70
Pro Gear 75W-85 replaces Sin Manual Trans
Pro Gear 75W-90 replaces Sin Gear Oil 75
Pro Gear 80W-140 replaces Sin Gear Oil 80
Pro Gear 85W-110 replaces Sin Gear Oil 110

I wouldn't use Pro Gear 85W-110 in a 4x4 that goes through a lot of water as the add pack is water soluble and it will then degrade the seals, otherwise it's an ideal viscosity for a lot of applications.
IMO there needs to be a lot more xW-110 gear lubes available, it's a great viscosity range and this looks like an excellent mineral based lube.

The ACEA have updated their specs too.
The new ACEA E9 specification has been introduced which requires much better aftertreatment capabilities for the oil compared to E7 oils, with slightly better wear, soot handling and corrosion protection and the same bore polish and piston cleanliness performance as the already excellent E7 oils.

At some stage I'll post up some excellent comparison charts from Lubrizol (the worlds biggest additive supplier) on how the different specs compare and overlap.

Since this has been bumped on the topic of Penrites....

Any reason I shouldn't run Penrite HPR 5 in my 300TDI?