Oil change intervals

slartibartfast

We have a Vermeer 352 stumper with the Diahatsu 34hp diesel engine. Mobil technical people have told us we can run it for 300hrs between oil changes if we use 5w30 Mobil 1 synthetic, this is double what we are getting using mineral 15w40.
Anyone else using it in diesels and does it make a difference?

Eric Frei

Over here they drove a ute some 40,000k's or so on mobil and cracked out the fastest ute record clocking up 271Km/h

Fastest Ute in the World, Holden HSV Maloo R8

Youtube video about the
The oil is good, but keep your air filters clean.

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Steve Tipton

I service machines every 100hrs.

Oil's cheap!

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Heightmaster

Eric Frei

I use a Penzoil semi synthetic 10W-30, in the grinder, ute etc.

Have tried a few, Valvoline, Penrite, Castrol, Mobil all in the same semi and viscosity.

I found the Penzoil stopped the ticking lifters the longest, at around 8000K after an oil change they start ticking again reminding me time is coming. However the other brands were much earlier.

With a mineral oil they tick like within 1000k of an oil change. A mechanic told me to get a semi synthetic and it would stop, so right he was.

The car I have owned for 7 years now, it's a 2.6L 4 cyclinder, pulls a trailer and stump grinder plus loaded tray everyday. It probably has 1.6 tonne on it all the time and at times more.

It has done 340,000KMs now and still not using much oil, not puff of smoke at start up, no puff between gear changes. Hats of to Mazda and Penzoil.

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treerat

Bucket truck, and F-750 get their oil changed at 3000miles and every October. Chipper 100hrs, stump grinder 50hrs and the wife's explorer when she nags that the change oil light comes on. I use what the MFG suggests. It may cost more but I know it is done right, and when it needs it.

rick

OK, first up, what are the manufacturers recommended oil specs, including viscosities ?
What ambients is the machine operated in ?
How long is it operated for and under what conditions ?
How much idling does it do ? (very important with diesels, idling is a killer)

The only way to determine extended oil change intervals is with used oil analysis. You take a sample and send it ff to the lab for analysis. It's what the big operators have been doing for forty years, and is the only way to accurately work out when to change lubes.

Secondly, M1 5W-30 only has a CF diesel rating. ie, it's ok for passenger car light diesels, but not a dedicated diesel oil by any stretch of the imagination IMO.
It's also an ILSAC GF-4 rated oil, this means that it's a fuel efficiency oil and so has a low HTHS of 3.09, (your 15W-40 will be over 4) and reduced ash additive levels to meet the API SM category.

What oil are you currently using ?
I'd take a sample at 150 hours and send it off to ALS (Australian laboratory Services) and ask for their 'Wear Check' analysis. You might be surprised to find that it can easily extend your oil change intervals with what you currently run.
A number of current mineral based diesel oils like Caltex Delo 400, Castrol RX Super, Fuchs Titan Ultra Lube, et al are capable of 30,000km oil changes in trucks when using UOA's.
Having said that, oils like Mobil Delvac 1 can go up to 100,000km in the same environment.
I've taken Nissan Patrols to 20,000km OCI's with Delvac 1 easily, and that was back when our diesel was still 500PPM sulphur, not the nice clean stuff we use today (>10PPM)
The recommended OCI interval is 5,000km on the old TD42T dinosaur, and interestingly Fuchs Titan Ultralube was hardly sweating at that interval either, it could easily go 10,000km and that was with heavy towing 80% of the time.

Bottom line is that dedicated diesel oils, even mineral based ones are a far more robust oil than passenger car oils, even synthetics like M1.
They have higher TBN's (total base number) which is an indication of an oils acid fighting ability and therefore life.
Advising a client to use an oil like M1 in a diesel, without first analysing what they are currently doing is irresponsible, then you have to sit down and work out the economics of changing to a good syn diesel oil to see if the extended change intervals that are possible are actually economically worth it.
In my instance they were, we were getting less wear with less oil changes when going to a dedicated heavy duty synthetic oil, but it doesn't always work out that way.

slartibartfast

Have been running on Mobil 1 for 50hrs now and find the engine starts easier and runs cooler and quieter. Will change oil and filter every 150hrs from now on.