Thread: liquid carbon

Originally Posted by miky

trailcutter...

Although the servicing book says 20 000km that is NOT for Australia.

Didn't they put a sticker on your windscreen saying 12 000 km?
Dealer also emphasised to me 12 000km.

yep ---but my sticker states 20000 k /12 mths.................. my sevice book states 20,000 for aust/1st world etc etc .............10,000 k service int ,,3rd world etc etc for ............... i,d have another look at book!!!!!!!!!

anyways i allways did my tojo diesels at 5 k ,,,,,........so i,ll carry on along those lines apprx.,,,,cheers

bought my tube of sikaflex today,,,,,,,time to fill the gaps ,,,,,,

Originally Posted by miky

Like trailcutter I have a new Puma and "they" say next oil change is at 12000km.

Now... On prevous new cars "they" say the first oil change should be a lot less than that, like 1000km.

Reckon it's ok to leave the first oil change to 12000km?

I was told by the dealer the engine is 'run in' at the factory. Hence no need to worry about 1000k oil change. As the car gets older, I personally like to change the oil every 5000 - cheap way of keeping the engine going longer if you are planning to hang on to it for a while.

[snip]
i allways did my tojo diesels at 5 k ,,,,,........so i,ll carry on along those lines apprx.,,,,cheers

Todays diesel is ULSD, with the sulphur <10PPM vs ten years ago when it was 500PPM and the engine is a common rail design with exception fuel control, why would anyone change oil and filters @5000km unless that's as far as you went in twelve months (or you travelled less than 20km/trip and the potential is there for fuel dilution)

I mean it's your money and you can spend as you wish but ??

Originally Posted by rick130

Todays diesel is ULSD, with the sulphur <10PPM vs ten years ago when it was 500PPM and the engine is a common rail design with exception fuel control, why would anyone change oil and filters @5000km unless that's as far as you went in twelve months (or you travelled less than 20km/trip and the potential is there for fuel dilution)

I mean it's your money and you can spend as you wish but ??

rick130,

Are you saying that the major wear factors for engines related to oil is fuel dilution and sulphur content?

I was under the impression that engine wear occured due to metal particles and silica from dust from the air ingestted getting in the oil and wearing due to the abbrassive mix. And that more frequent oil changes reduced the wear on engine due to the more frequent removal of the abbrassives in the oil.

And as for an earlier post on changing oil more often on an older engine, I think it would be too late by then as most of the benefit would come from good maintenance in the earlier part of an engines life when the greatest amount of wear occurs until the engine beds in.

If the air cleaner is doing its job, silica/dust ingestion shouldn't be an issue. (as long as you aren't running a K&N or foam filter)

Fuel dilution is an issue, mainly with short trips/low operating temps, low sump capacities and leaky injector O rings, so that's one place that short OCI's can help if you don't know it's happening.
(Direct injected petrol engines are having big fuel dilution problems, but that's another story)

In the past the sulphur from uncombusted fuel caused most of our oil breakdown problems, hence the high TBN's and the high metallic ash additive levels of most diesel oils to combat sludge and soot, but with ULSD this is a thing of the past, and as a consequence TBN's are coming down and low SAPS oils are here now with at least as good wear protection as the older, high ash oils.

Metallic wear levels shouldn't be an issue if the oil is doing it's job (all things being equal)
In large trucks Fe (iron) along with soot, TBN (total base number) and TAN (total acid number) is generally used as the condemnation markers for oil change intervals, but in highway trucks with premium syn oils we are talking about 100,000km+ oil change intervals, although they do have large sump capacities too.

Put it this way, before we dropped to 50PPM sulphur diesel I used to run our TD42T Patrol, a dirty, indirect injected engine, out to 20,000km easily on Mobil Delvac 1.
Admittedly that engine has a 10.5 litre sump and two oil filters (one a combo with half being a by-pass filter) with wear metal numbers no where near any condemnation limit. Wear metal numbers were hardly changed from premium mineral oils @ 5000km.
At the time the vehicle was primarily used for towing horses between here and Sydney, so wasn't used lightly, but was used for long km when running.
When under warranty it was a nightmare doing an oil change every two and a half to three weeks (5,000km)

These days with mainly short trips I've brought it back to 10-12,000km, it's now clocked over 320,000km and still runs sweetly.

It's due an oil test, so it'll be interesting to see how it looks, but I don't expect much to have changed.

Originally Posted by slug_burner

rick130,


[snip]And that more frequent oil changes reduced the wear on engine due to the more frequent removal of the abbrassives in the oil.

[snip]

Further to above, the soot in the oil from the high sulphur content fuel was the high abrasive factor.
Think of it this way, soot = carbon, carbon = very hard abrasive.

This is where the centrifuge filter on a TD5 is brilliant, they keep the oil incredibly clean.

Thanks Rick etc

People who insist on 5k intervals are living in the dark ages!!!!

Even with no oil changes I've seen vehicles go 100,000km !

The oil was bad, but the engine was ok. A flush and new oil and all was good. Will it make 200k who knows but modern engines and modern oils are very different from those of old.

thanks for the data specific,,,,,allways had tojo diesels,,but have had a 5 year break trying out a petrol,,,,,,,,,,,,,,all things being equal i suspect your right,,re; lube intervals,,there is a point where you begin to throw money away,,,things have come along,,,,,,in my opinion sump capacitys r a big factor in this equation,,,,,,,

whats the story with no zinc oils and can someone tell me sump capacity of my 110 2010 ,,as i have no comprehensive spec sheets..yet.cheers