Any difference in oils for Diesels??

As I know it, the grade and the viscosity are the main factors it seems - then you choose the brand. Grades change for the various engine types - all to do with what the manufacturer recommends - fuel types mean a lot too I guess. Isuzu specify a CG-4 grade for my Jackaroo TD, with a range of viscosities that can suit varying temperature zones. I use Castrol Magnatec 10W-40 but there a quite a few others makes that would be suitable. There are a few expert sites on the topic - eg.
http://www.carbibles.com/engineoil_bible.html

Just looking at that bibles site - seems like the CG-4 designation would best be termed the 'category' (there's about 13 of them listed) - grade is still commonly used in reference to viscosity.

Diesel's use 'different' oil to petrol engines, which can be seen in the oils technical specifications. The viscosity is not the main difference as often it's similar or the same.

That's why some oils are rated for "old" engines, some for "new" engines and some for "Diesel" engines which produce soot and require a cleaning agent added which is not in the oil for petrol engines.

Signman, just recently I asked my mechanic son whether he would service our D40 t/diesel Navara. Yes, and he would look up what the required grade of oil was required as specified by Nissan.

The son suggested that we run a fully synthetic oil which covered the grades required by Nissan. No worries I said, go for it.

And I'm glad I did. He chose Mobil 'Delvac 1' and we purchased 15 litres (enough for 2 oil changes) for $150 which I reckon is pretty damn good.

Well we changed the oil and pretty much changed the engine.
From cold it felt as if it had been driven for half an hour. Very smooth, much quieter, and pulled as though it had been warmed up. The mileage on the tank increased from 700ks (before warning light comes on) to over 790ks and the light still hadn't come on.

I thought how grouse is this? The oil exceeds the manufacturer's recommendations, makes the car perform better and much more economically in the process.

Check it out, I can't recommend this oil high enough.

Cheers, True Blue.

Signman,
Firstly, a disclaimer - I'm no expert, but this is the way I see it and welcome any corrections.

The difference is in additives. Put simply, diesel oils have more detergents to handle soot better. Petrol engine oils also contain detergents, but its not as critical.

Your 1Hz is an old fashioned indirect injection diesel, so it produces a bit more soot than the modern direct injection diesels. You'd be better off with a diesel engine oil, as soot can lead to oil thickening.

Many diesel engine oils are marketed as mixed fleet - so can be used for petrol as well as diesel vehicles.

If cost is a major consideration, a 15W40 Ci-4 mixed fleet oil like Fuchs Universal HD , or Gulf Western Top Dog will be fine in your 1Hz. I buy them for under $80 for 20litres from the truck shops.

Cheers
Phil

There are a million reasons hy you shouold type Engine OIL into the the forum search bar, and look what happens.
A million different Ideas, but what they are basically telling you is to read your owners manual, and only use the recomended oil, with the specifications.
That way you should never go too far wrong.

Cheers Mate

Bucky