Oil sludge, a solution ??

[earthworm]

Both turbocharged(Saab,VW) and n/a(Toyota) engines suffer from this sludging problem.

And the solution I have yet to see.

I believe this is caused by oil temperatures being either too high (the turbo in action) or too low (winter in action ?)..

I think that the formulas of some oil, otherwise perfectly good, cannot handle this sludge.

The OCI should be determined by how long the oil spends in a less than ideal state.
Analysis should bear this out..

 

[IslaVistaMan]

Not all Toyota engines sludge. Go here to find those that do:

http://www.yotarepair.com/Sludge_Zone.html

Oil temperatures play a part, yes, but overly long oil change intervals (and a perceived lack of crankcase ventilation) were the real causes of the problem.

 

[TR3-2001SE]

I think the answer is two fold. You use a very good synthetic oil and you monitor your change interval with UOA's to see how it it doing. We have seen even the best synthetics fail if pushed to far in these sludge monsters.

 

[glennc]

It would be interesting to know the predominant causes of sludging. Localized heating? A tendency to keep the oil too cool for too long causing oxidation? PCV contaminants?

Obviously there is something fundamentally different in engines susceptible to it. If we could figure out the cause it would be much easier to figure out a solution.

- Glenn

 

[wavinwayne]

It's easy to figure out at least one reason for the VW/Audi sludge-makers (Passat 1.8T & Audi A4): Insufficient oil capacity + use of non-VW approved oil + 10k mile OCI's = sludge.

 

[earthworm]

The reality is that most car(appliance) owners are averse to spending any money on their cars, the car-maker helps not by playing up to them with the extended OCIs.

For them, maintenance is checking the air pressures and checking "under the hood" during refueling.
And having the gas jockey do this for free!!
Of course this may no longer occur as the gas jockey is a thing of the past.

So, does Oscar the Owner go to the dealer and pay $$$ for the OC or does he pay just $$ (at the Quickie-Jiffy OC place)...
And it is very poor advice for the man just to use the dealer, or else !

 

[blmqzjc]

wavinwayne,

I have a Passat 1.8T and agree with your post. I am confused, though, why this sludge problem apparently doesn't exist in Europe, only in the good ole USA. Their OCI's over there are at least as long as ours, the engine is the same, the oil is the same (I think), so what's left? Maybe $6/gal gas really is better!

 

[earthworm]

IMO, the Europeans do take better care of their cars.
Plus, I suspect(strongly) that their mechanics are more knowledgeable.

Our society is, IMO, more open, theirs, not as open, so when something embarrassing happens, they can cover it up better than we can...

There must be some English or Germans on this forum to refute what I say..

Some of the European oil is the same, I am sure, but other oil (GC) is not..

I still hold to the temperature theory, but agree that many OCIs are way too long..
And like everything else, this must be proven via the oil analysis..

The king's word no longer suffices, particularly in America....

IMO, VW is insane in recommending a 10,000 mile OCI, if in fact they even do this...

 

[55Test]

Something that's been on my mind, I've seen websites that list the Toyota 5SFE as being a sludger. To the best of my knowledge, the 5SFE is essentially the older 3SFE that's been bored and stroked or something. Since the 3SFE uses the same type of belt-and-gear driven dual camshaft setup that the 5SFE uses, and I believe I've read that is one of the reasons the 5SFE is a sludger, would it stand to reason that the 3SFE is also a sludger?

 

[ekpolk]

The two habitual sludgers were the 5S-FE and early build 1MZ-FE (I-4 and V-6 respectively). Earthworm, these are the only Toyota engines with a pattern of sludging where they shouldn't. In fact, if you review our UOA section, you'll see plenty of evidence of how cleanly Toyota engines run, as a whole. The 2UZ-FE V-8 is arguably the best engine we've ever seen, with respect to staying clean and not sludging. 55, I can't speak to the 3S engine, all I can say is I've never heard of it being an issue. Reasoning from the facts we have, I can only assume that one or more of the surely many changes made as the 5S evolved from the 3S were contributors to the 5S being prone to sludge.

Whether or not oil breaks down in any given application is a result of the combination of perhaps hundreds of factors, including basic engine design, oil used, driver habits (driving, maint, etc.), climate, and so on. Some things will be more substantial contributors. All you can do is know your engine and car, think through how you use them, and make safe prudent choices. VW is not insane, nor is Porsche with their 20,000 mile OCI (we've seen a 20K mile Porsche UOA here, a Cayenne, it was fine). It's the owners and techs who didn't follow the program, and after the fact they blame the car maker. Maybe they were insane for assuming their customers and dealers would follow their requirements and recommendations. . .

 

[Quattro Pete]

quote:

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the oil is the same (I think),

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Well, that's the thing, the oil is not the same. For years, the VW/Audi dealers in the US were feeding cheap bulk dino oil into these engines, and the manual did not specifically require synthetic oil. They've changed their practices now, but the damage has been done.

 

[John_E]

The real test is whether a longitudinal 1.8T engine (4-qt. sump) will sludge/coke up on a 502.00 synthetic oil with a "by-the-book" 5k mi / 8k km OCI for "normal" driving, somewhat tighter for short city trips. If it happens in the U.S. but not in Europe, then I can only suspect the higher sulfur content in our gasolines.

My theory is still that conventional sludge forms from short trip driving, and then burns into coke in the turbo, although I believe dino oils sometimes burn directly into coke.

 

[Ken2]

The sludge can be cleaned with Auto-Rx.

The sludge can be prevented with the right synthetic oil. Not any synthetic qualifies for any engine. Look at all the specs for VW/Audi, Mercedes, GM/Saab. Some European engines require manufacturer approved oil.


Ken

 

[peterr]

quote:

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VW is not insane, nor is Porsche with their 20,000 mile OCI (we've seen a 20K mile Porsche UOA here, a Cayenne, it was fine).

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ekpolk

While I was surprised to hear a Porsche rep recently indicate an OCI of 25K to 30K kilometres was recommended, I guess it is more likely if you follow these steps:

"Take 11 litres of Mobil 1 0w40..."

Porsches typically seem to have a sump capacity of about 3 litres per litre of engine displacement and a bigass filter. While I am not an expert on sludged engines it seems that a lot of them have 3.5 litre sumps.

 

[Big Jim]

Just for giggles I'd like to pass on about my daughter's Mini Cooper (not a Cooper S).

She took it in to the dealer for a recall a few days ago. She has free maintenance. It came with a factory free maintenance package, and she extended it through the entire warranty period.

It has an oil life monitor. The first oil change came up at 10,000 miles. That somewhat alarms me. I talked her into latting me change it for her at 15,000 miles (Mobil 1 5-30, same as the dealer). It is now approaching 25,000 miles. The oil life monitor shows it still have 1750 miles remaining until it needs an oil change. The service advisor agreed to do it for her while it was in. That means that the oil life monitor would have left it in for aproximatly 15,000 miles! I did not reset the oil life monitor when I changed the oil.

This is the scary part though, the service advisor said she had seen a few that went nearly 30,000 miles before the oil life monitor triggered the need for an oil change. That's scary!

 

[Paranoil]

quote:

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the service advisor said she had seen a few that went nearly 30,000 miles before the oil life monitor triggered the need for an oil change. That's scary!

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Only if the dealer/owner uses the wrong specification of oil.

12,000 to 15,000 mile OCIs are the norm in Europe for 'normal' engines (some high performace engines are in the 6 to 10K range), with several manufacturers now push that to 20,000+