Is it true that used up oil ruins seals and gaskets ?

[OM605]

I guess it has always been the reason i don't follow the 15k kilometers OCI as recommended in my car's owner manual regardless of the fact than a modern 229.5 synthetic is obviously far better than the required 229.1 and would hold up well in my case (small engine, 6 quarts sump, mostly highway driven).




Any opinion on this guy's opinion (and experience) ?

I remember seeing a video from Eric The Car Guy where he shows an engine with destroyed gaskets and puts it on the account of infrequent oil changes (more than 5k miles).

The dude seems to live in a world of engines destroyed by 10k oil changes but looking up forums like Benzworld there are many people with similar cars doing nothing but 10k on Mobil 1 or whatever synthetic for years and hundreds of thousands of miles while not complaining of any leak or even oil consumption.

 

[MontePrix28]

I've never seen a engine that is spec'ed a 229.5 fail because of an oiling related issue if the proper OCI is followed (10k miles for Mercedes, some older ones were 13,000 miles). Usually seals/gaskets fail due to common issues/design flaw or "that gasket always goes by X miles or X years". Regarding the seals, front cover gasket/cam adjuster gaskets on M272 and M276 engine always leak eventually, as does the air/oil separator on the back of the block, no matter the customer's oil changing habits it seems.

It may seem that owners with worse "oil change" hygiene also have leakier engines, but it's (to me) because they are less likely to have them resealed/fixed and usually just let them leak, thus the "correlation" of longer ocis=more seal degradation.
I work at a mercedes dealership.

 

[NewtonPulsifer]

It’s the dirt. The never changed air filters and unfixed vacuum leaks. Of course those people never change their oil either so carbon from stuck valve stem seals ends up joining that show. It does a number on gaskets.

A course of Gumout Multi, air filter change, and a diet of Valvoline HM has turned leaks to seeps in my experience.

 

[OM605]

I've never seen a engine that is spec'ed a 229.5 fail because of an oiling related issue if the proper OCI is followed (10k miles for Mercedes, some older ones were 13,000 miles). Usually seals/gaskets fail due to common issues/design flaw or "that gasket always goes by X miles or X years". Regarding the seals, front cover gasket/cam adjuster gaskets on M272 and M276 engine always leak eventually, as does the air/oil separator on the back of the block, no matter the customer's oil changing habits it seems.

It may seem that owners with worse "oil change" hygiene also have leakier engines, but it's (to me) because they are less likely to have them resealed/fixed and usually just let them leak, thus the "correlation" of longer ocis=more seal degradation.
I work at a mercedes dealership.

I was under the impression that with my engine being 23 years old and seeping a little bit already it would make everything worse to extend the intervals that much. This engine is very healthy however.

 

[demarpaint]

Neglect by failing to change the oil, or run it too long will cause all kinds of issues. I don't see much of an issue with gaskets, but I'd imagine seals might take a bigger hit. Especially a seal on a rotational part, RMS and a few others come to mind.

 

[OilUzer]

I think seals take a bigger punishment by an imbalanced real (or is it closer to real?) synthetic oil.

 

[OilUzer]

@3:30 First video
curious if there are any "professors" at "oil plants"?
is there such a job title?

He sounds like one of my uncles. Always angry but a good guy ... lol

 

[Gebo]

Louis Altazan of Agco Automotive in Baton Rouge says they are seeing so many more engine repairs since car manufacturers started
increasing the OCI. Many more leaks. He says with the 3k-5K OCI it was very rare to see a car needing engine repairs.

 

[ABN_CBT_ENGR]

Any opinion on this guy's opinion (and experience) ?
I remember seeing a video from Eric The Car Guy where he shows an engine with destroyed gaskets and puts it on the account of infrequent oil changes (more than 5k miles).

Yes, his "opinions" for all intent and purpose are fundamentally and fatally flawed at every level and most of the "mechanic level" analysis out there falls under the same umbrella. At best its an honest (yet unqualified ) opinion based on an anecdotal visual examination of a seal by those who are not qualified to conduct such an analysis and at worst just an ego driven rant for attention.

Let me defend and qualify my statement.

I do industrial forensics and gaskets/seals are a big part of it ( excluding mechanical seals for this discussion) and contract with almost every OEM for both so that's a very broad view and detailed information from them and their own testing.

You will see this analysis much more in industry than on the average car because the daily driver isn't subject to all the process conditions and chemicals gaskets/seals are in industry and the average oil isn't sometimes $200+ a gallon, The average car doesn't cost a few million and when its not running the average car doesn't cost production of $10k's per hour till its fixed and the repair bill ( total cost of failure) isn't $100k + per leak. ( that's assuming no environmental issue)

Point is we do quite a lot of it and have to be right when we submit the corrective plan.

Except in the rare case of "infant mortality" ( failing almost immediately) of a seal or gasket where there was a complete error in application due to temp, composition, chemistry or other factor- the actual oil and whatever properties it may have or even develop has virtually nothing to do with the failure of a seal or gasket. Even with most contamination ( defined as chemical)

Seals typically fail from

Abrasion ( particulate matter grinding, shaft abrasions etc.)

Fit (can be anything from dimension too small for proper seal tension, egg wear of shaft, misalignment creating a gap)

Installation (cocking a seal, damaging the garter spring/element)

Heat ( over time this will fatigue any polymer)

Dry Running ( a seal needs a bit of lube to live- its not a quality of the oil but the long term absence leading to abrasion and/or thermal fatigue)

Pressure ( usually seen as an extrusion but can be just blow by)

Normal end of life ( no polymer compound lasts forever with all properties intact)

I left off things like mechanical damage because those failure modes are usually random and external to the seal proper.

Basically the same for gaskets but gaskets are prone to set and need retorquing evenly, sometimes they saturate/delaminate ( even rot)

Sometimes a change to a much different fluid that's thinner or a temp change will leak at certain grades but not at others.

So, to say a gasket or seal failed due to an oil, extended oil change interval or some "normal to that application" contamination- while POSSIBLE would be at the highest end of improbable and require significant supporting hard evidence to prove it.

 

[Jetronic]

In cars, and especially diesels, the longer you extend the oci the more change you get of overloading the oil with soot. I don't think soot is much of an issue in industry applications. Nor is fuel dilution.

Now wether the soot is or becomes abrasive or not is another thing. But I regularly get cars in for a service who have oil and soot trails coming from crank seals but after the oil is changed they often don't return. I clean the oil off and let the customer come back after a week or two to inspect the leaking if the car is still under warranty and the leak didn't immediately return.

So old oil can leak, but 80% of the time it doesn't cause immediate seal failure. Id just like to make sure it won't lead to a big repair after warranty is over.

 

[MrQuackers]

I know what Frank Barone would say if he saw that filter.

 

[OM605]

Very interesting answers from you guys. What's curious is the number of people doing 10k oils changes without having issues. Browsing over the UOA section i see so much high mileage cars doing 10k or longer intervals without issues. Same thing on Mercedes forums with people following the 10K miles / 15k kilometers and not complaining. It's like there are two different realities.

 

[Jetronic]

I should take some pictures from inside the oil filler for the first maintenance at 15k km. Then think how what you see there accumulates every oci like that.

diesels stay fairly clean over that mileage but gas engines turned red from varnish deposits and sometimes have coking on the oil filler cap.

 

[ABN_CBT_ENGR]

In cars, and especially diesels, the longer you extend the oci the more change you get of overloading the oil with soot. I don't think soot is much of an issue in industry applications. Nor is fuel dilution.

Now wether the soot is or becomes abrasive or not is another thing. But I regularly get cars in for a service who have oil and soot trails coming from crank seals but after the oil is changed they often don't return.

Just on those points

On the rolling stock side, as much as a car- everywhere else pretty much zero.

Doesn't change anything though because "soot" ( carbon particles) are not significantly different in terms of how they damage a seal than any other abrasive and "fuel" not different than most solvents and/or process chemicals and they are both present almost universally just in different concentrations. Thinning a lubricant to the low end of the seal selection will make it go from a class 1 to a higher class leak PDQ

Also remember on lip seals- the manufacturer designs then to weep and all of them will tolerate a bit of contamination ( otherwise they would leak almost from the beginning). Additionally large contamination is too big to get into the barrier fluid at the faces and too small will flush right through with no damage so there is a median size that has damage potential which should be reduced by the filter significantly.

 

[OM605]

Jetronic, all the sludgers i had were gassers and i've always been amazed by the total absence of varnish or build up in the diesels i had, including my old W124 with almost 500k kilometers which had 10/15k kms oil changes on dino. I would love to understand why.

 

[OilUzer]

Yes, his "opinions" for all intent and purpose are fundamentally and fatally flawed at every level and most of the "mechanic level" analysis out there falls under the same umbrella. At best its an honest (yet unqualified ) opinion based on an anecdotal visual examination of a seal by those who are not qualified to conduct such an analysis and at worst just an ego driven rant for attention.

Let me defend and qualify my statement.

I do industrial forensics and gaskets/seals are a big part of it ( excluding mechanical seals for this discussion) and contract with almost every OEM for both so that's a very broad view and detailed information from them and their own testing.

You will see this analysis much more in industry than on the average car because the daily driver isn't subject to all the process conditions and chemicals gaskets/seals are in industry and the average oil isn't sometimes $200+ a gallon, The average car doesn't cost a few million and when its not running the average car doesn't cost production of $10k's per hour till its fixed and the repair bill ( total cost of failure) isn't $100k + per leak. ( that's assuming no environmental issue)

Point is we do quite a lot of it and have to be right when we submit the corrective plan.

Except in the rare case of "infant mortality" ( failing almost immediately) of a seal or gasket where there was a complete error in application due to temp, composition, chemistry or other factor- the actual oil and whatever properties it may have or even develop has virtually nothing to do with the failure of a seal or gasket. Even with most contamination ( defined as chemical)

Seals typically fail from

Abrasion ( particulate matter grinding, shaft abrasions etc.)

Fit (can be anything from dimension too small for proper seal tension, egg wear of shaft, misalignment creating a gap)

Installation (cocking a seal, damaging the garter spring/element)

Heat ( over time this will fatigue any polymer)

Dry Running ( a seal needs a bit of lube to live- its not a quality of the oil but the long term absence leading to abrasion and/or thermal fatigue)

Pressure ( usually seen as an extrusion but can be just blow by)

Normal end of life ( no polymer compound lasts forever with all properties intact)

I left off things like mechanical damage because those failure modes are usually random and external to the seal proper.

Basically the same for gaskets but gaskets are prone to set and need retorquing evenly, sometimes they saturate/delaminate ( even rot)

Sometimes a change to a much different fluid that's thinner or a temp change will leak at certain grades but not at others.

So, to say a gasket or seal failed due to an oil, extended oil change interval or some "normal to that application" contamination- while POSSIBLE would be at the highest end of improbable and require significant supporting hard evidence to prove it.

how about seal damage or degradation due to chemicals? I've read that syn oil (pao or ester? can't recall) is harsh on seals if not properly balanced with seal conditioners or softeners, etc.
is that true?

Also who is testing for all these chemical reactions e.g. seal compatibility? They keep pumping out new oil to consumer and how can you test the oil for 10-20 years if they are constantly changing or tweaking the formula?

 

[ABN_CBT_ENGR]

how about seal damage or degradation due to chemicals? I've read that syn oil (pao or ester? can't recall) is harsh on seals if not properly balanced with seal conditioners or softeners, etc.
is that true?

Also who is testing for all these chemical reactions e.g. seal compatibility? They keep pumping out new oil to consumer and how can you test the oil for 10-20 years if they are constantly changing or tweaking the formula?

Good points all and I’ll be happy to address them and this is pretty much across the board as I deal with all of the major manufacturers and this is a routine thing for an in depth lube audit and assessment and I do it frequently for compatibility with lubricants, environmentals and process fluids. Same thing applies to a lot of elastomers used in couplings.

Your question regarding chemical sensitivity is absolutely correct and must be diligently checked but also viewed in context with the whole.

All seals have a chemical tolerance chart by part # (you could DL either the SKF or Garlock manuals or see how deep this goes) and it will tell you pretty much everything. Then there is the engineering service to email for those unique ones.

If exposed to an incompatible fluid, no amount of additives is going to do anything but buy you a short amount of time. There is a very significant difference between a chemical attack against a polymer not rated for it and normal chemical degradation- the trick knows the difference. (It’s seldom obvious unless failure happens very quickly)

Seal analysis involves a battery of visual and physical tests, melt tests, durometer tests and chemical ones to determine failure modes- anyone who doesn’t do all these things is not capable of making an actual diagnosis as tow why a given seal did fail or be able to differentiate between a ‘failure” versus a normal “end of life’ event.

I will tell you who is doing all that testing (some in house- some outsourced)- both the oil companies and the seal companies. Neither one wants to introduce a product with unknown reactions nor neither wants to be on the business end of litigation resulting from such a negligent failure. They cooperate with each other too when asked.

I believe you will find the bulk of these “alleged’ seal failures due to the oil simply aren’t and probably 90% of the remainder that are are a direct result of the individual not doing the proper checking and mismatched them in the first place. ( not really a failure mode or mechanism that one can legitimately assign to the oil or seal as the human is supposed to think and check)

 

[UncleDave]

Varnish can harden seals if you let it get that far with the old oil.

"Stevepitbull" seems to have a lot of experience and appears to have seen lots of problems.
He is also trying to be a bombastic personality online. Pretty safe for Steve to make a call at 5K.
Most likely wasteful if the OEM calls for 10, but a safe call for his business and clients, as well as one that keeps them coming in semi frequently.
As an aside on Stevepitbull I think cosworths are neat and Im sure I'd enjoy hanging out with him if he can turn the volume down.

Between what the lab tells me and Stevepitbulls opinion, I'm going to go with the lab.
Between Stevepitbulls opinion and the Honda Oil life algorithm and monitor engineers - I'm going with the Honda engineers.

Been doing 10K on the Lexus (138k) for years now in a mix of 20/30/40 - at 10K the oil is still gold and I can easily see the stick.
The Ridgeline's fairly new (32K) and its OLM has called for a change in the 9K's on 0W-20. Its dark but I can still see the stick through the oil.
The titan (103K) 7500-10K, on 30EP, or 0W40- at 10K It's still gold and can see the stick through the oil.

A leak down is the only true test of tightness, but I can report no differentiated oil consumption and identical mileage to new.

UD

 

[NewtonPulsifer]

Very interesting answers from you guys. What's curious is the number of people doing 10k oils changes without having issues. Browsing over the UOA section i see so much high mileage cars doing 10k or longer intervals without issues. Same thing on Mercedes forums with people following the 10K miles / 15k kilometers and not complaining. It's like there are two different realities.

I actually do 15k miles OCI on my Mercedes (UO analysis was fine). You’ll find that I’ve changed the plugs once preventatively (even though a huge PITA on that car), change the air filter regularly and use quality ones, promptly fix rather than ignore any issues that could stress the motor (tiny vacuum leak, failing O2 sensors etc.) and run injector cleaner every 4 tanks of gas. Oh and flush with BG EPR or Gumout Multi every 30k miles in the oil sump before the oil change.

So basically I don’t extend the OCI on vehicles unless I’m sure it is running tip top.

Then there’s people who ignore the flashing check engine light and the 30% drop in mpg.....

EDIT: Oh and Italian tuneups are a help IMO. So manumatic on automatic trans is essential.

 

[OM605]

NewtonPulsifer, That's how i treat my cars too. I only use Mann or Hengst filters and do an occasional italian tune up (made some engines behave noticeably better in my experience). I clean my injectors in an ultrasonic bath while i'm in the process of other maintenance like sparkplugs since they're so easy to get to. My engine is very healthy but just exhibits a light seepage around the main seals and/or the oil pan gasket, which is my reason for the 7k kilometers OCIs on semi 10W-40 i do now instead of the 10k i normally do on syn 5W-40 (but still considering testing the recommended 15k as scary as it sounds to me).