Does diesel oil do more cleaning?

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Maybe all of my threads are going to be towards diesel oil, since I plan to change oil in the Civic soon.
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Do oils like PP5W30 Euro AV do more cleaning than any other gasoline oil? For short tripping and 3K miles, would it clean anything or cause harm or no noticeable difference for a car like Civic?

I have no qualms using it, based on the thread I posted: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4620526#Post4620526

Thanks for any advice and help.



 
Define cleaning.
Define the measurement of said cleaning.
Provide a method for measuring said cleaning action.
Report back with repeatable test protocol and verifiable, repeatable results.
Discuss.

Or..... speculate.....
 
I think all modern oils do a good job at cleaning with a shortened OCI. There’s really no way to say which oil cleans better. All you will find is opinions.
 
My understanding was always that because diesels are sooty, the diesel rated oil has to be better at dispersing vs pcmo. I'm sure people that know can correct my assumptions.
 
Many of the guys on the BMW forum swear by Rotella T6 (diesel oil) to clean out the ring lands which reduces oil burning. I always thought it was due to the high magnesium content.
 
NONE of the major oils will put anything on their oils that say they "clean" dirty engines.

Pennzoil Ultra Platinum & Platinum say they "keep pistons xx% cleaner" than the standard.
Castrol Ultraclean GTX says it provides "50% more sludge protection"

There are other examples. Only a solvent can clean. Good oils can only reduce the amount of junk that gets deposited into the engine.
 
For 3k mile intervals in a Civic, use the cheapest name brand conventional oil on clearance. I pay for expensive diesel oil only when I have an application that I have to use it for DPFS and soot. You don't have that so save your money.
 
Originally Posted By: SubieRubyRoo
NONE of the major oils will put anything on their oils that say they "clean" dirty engines.

Pennzoil Ultra Platinum & Platinum say they "keep pistons xx% cleaner" than the standard.
Castrol Ultraclean GTX says it provides "50% more sludge protection"

There are other examples. Only a solvent can clean. Good oils can only reduce the amount of junk that gets deposited into the engine.


I’ve seen oil filters cut open on a dirty engine after short synthetic OCIs. There is certainly some cleaning going on. Lots of black grit.
 
Originally Posted By: 1JZ_E46


I’ve seen oil filters cut open on a dirty engine after short synthetic OCIs. There is certainly some cleaning going on. Lots of black grit.


But a "dirty engine" has 1000 times more black grit sludge still in the engine....
 
Port injected Civic with how many miles and what service history?

You want clean, put a full can of BG109 in there for teh last 100 miles and change the oil. Or, put 5 ounces of SeaFoam in the crankcase for a 20 minute gentle drive around the block and change the oil. Either will clean stuff no basic oil will touch.

But what are we trying to clean? Varnish? Sludge? Something else ...
 
HDEOs do have a healthier dose of dispersants, since when used in Diesel engines they are pumped ful of soot they have to keep in suspension.
I am using a HDEO in my Escort to hopefully help clean it up, the previous owner did not change the oil regularly, although i intend to keep using HDEO for the high Zddp and the 15W-40 viscosity is perfect for the CVH with over 100k miles.

Rocker cover gasket change 09-05-2018 by Argentum Enim in Sempiternum, en Flickr

Took the valve cover off the other day to change the rocker cover gasket, the valvetrain itself was not too bad the but the underside of the rocker cover was caked in oil deposits and the PCV outlet was clogged.
 
Originally Posted By: JeffKeryk
From:
http://www.machinerylubrication.com/Read/28576/comparing-gasoline-diesel-engine-oils-

Diesel engine oil has more additives per volume. The most prevalent are overbase detergent additives. This additive has several jobs, but the main ones are to neutralize acids and clean. Diesel engines create a great deal more soot and combustion byproducts.



It is received wisdom that overbased metallic detergents carry out a 'cleaning' function in engine oil. In my experience, this just isn't true.

To understand what an overbased detergent actually is, try and imagine a beaker which contains one third powdered chalk (calcium carbonate) and two thirds of mineral base oil. The resultant gritty, opaque, gooey mess might not be something you'll want to put into your engine if your objective is keeping things clean! It would also block your oil filter in minutes.

Now imagine you can remove from the beaker a bit of the base oil, and replace it with some 'neutral' calcium alkyl sulphonate (often referred to as 'soap') which, through the magic of colloidal dispersion, breaks up those particles of calcium carbonate to the point where they're soooooooooooo small, the mixture becomes transparent. That's essentially what an overbased detergent is.

The primary purpose of the calcium carbonate in detergent in to neutralise acids (just imagine putting citric acid in your kettle to react with limescale...same thing!). The primary purpose of the calcium alkyl sulphonate is to colloidally disperse that inorganic base (hence the term 'overbased'). Now some folks will tell you that the same calcium alkyl sulphonate will keep those acid-base reaction products dispersed in the oil and help prevent deposits dropping out. I think at one point this was probably true but in today's environment, I'm not sure it is and if it still is, then it's a very minor effect.

Hope that helps...
 
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OK, so now we've got one of the site's foremost EU tribologists on record saying true "cleaning" effect doesn't exist... Mola is the other one I'd hope to weigh in on this, but he hasn't. How long will people continue to psychologically grant undue magical powers to oils when even their own manufacturers don't claim the benefits as a selling point??

In this day and age of selling EVERYTHING... don't you think EVERY oil company would hop on the cleaning bandwagon and ride that pig for all it was worth if they knew they couldn't get sued for claiming their oils "clean" dirty engines?? C'mon, peeps, this is BITOG... any amazing properties to be had from engine oil have been run through several legal departments and vetted more thoroughly than DNC chairwomen... so if they ain't claiming it on the bottle, it ain't gonna happen.
 
Originally Posted By: SubieRubyRoo
OK, so now we've got one of the site's foremost EU tribologists on record saying true "cleaning" effect doesn't exist... Mola is the other one I'd hope to weigh in on this, but he hasn't. How long will people continue to psychologically grant undue magical powers to oils when even their own manufacturers don't claim the benefits as a selling point??

In this day and age of selling EVERYTHING... don't you think EVERY oil company would hop on the cleaning bandwagon and ride that pig for all it was worth if they knew they couldn't get sued for claiming their oils "clean" dirty engines?? C'mon, peeps, this is BITOG... any amazing properties to be had from engine oil have been run through several legal departments and vetted more thoroughly than DNC chairwomen... so if they ain't claiming it on the bottle, it ain't gonna happen.



It sounds like Mola has 'left the building'...

https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4752132/2
 
Originally Posted By: SubieRubyRoo
OK, so now we've got one of the site's foremost EU tribologists on record saying true "cleaning" effect doesn't exist...

In some respects, and perhaps SonofJoe agrees, there is "some" cleaning possible - it depends what you are expecting to clean. A bit of sludge might be removed from frequent oil changes. That's hard to avoid, in fact, if an engine is sludged and you do some rapid changes; some sludge will be coming out. Now, varnish is another matter, as is coking.
 
Garak, all due respect, I don't think we want to confuse "cleaning" with "flushing"... IMHO you can get the same "flushing" effect using even the PQIA warning oils by changing it frequently enough. That doesn't actually mean you'd want those oils in your engine for any length of time!
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