Is their such thing as a bad oil???

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I am thinking LUCAS or RP would be the most controverscial engine oils, but seriously if someone is using ANY dino that is rated for their car & changing at 5k or less, or ANY blend and changing at 7500k or less, or ANY full-syn and changing at 10k or less, then is their an brand or type of oil that we can say is more prone to cause more engine wear or sludge or problems of any kind; or just a "bad" choice?

If the answer is "no" then what are we all doing here LOL
 
No. There really isn't bad oil. There is wrong choice of oil due to weight or weather. We are here to discuss what the best oil is for what conditions, cars, driving habits etc. Not the other way round.
 
Not on the motoring North American general public's retail shelves.

Q.

p.s. I've seen some pretty poor quality motor oils in places such as mainland China, Thailand, Malaysia, some mid-east countries, etc.
 
Royal Purple is controversial, but it cleaned my motor pretty well. I put it in along with a FRAM (I blame both on not knowing about this site yet) filter as soon as I got my truck. I cut open the filter at 1000 miles and it was filled with big chunks of junk. Of course I didn't know what oil was in there before and for how long... Still not worth 8-9$ a quart by far though
 
How about the generic stuff at the dollar store or at 7-eleven?

The 7-Elevens in my are carry heavy PYB and either some generic stuff or 7-eleven branded oil.

When its 3 AM and your dipstick is dry.
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now, there certainly are some bad engines!
In fact, Amsoil issues a TSB recommending short OCI's on certain "sludge" engines. on my DC 2.7 Amsoil recommends 3k miles! also on the dodge 3.9, 5.2, 5.9 and 5k on certain vw, toy, lexus, saab models
 
Originally Posted By: tomcat27
now, there certainly are some bad engines!
In fact, Amsoil issues a TSB recommending short OCI's on certain "sludge" engines. on my DC 2.7 Amsoil recommends 3k miles! also on the dodge 3.9, 5.2, 5.9 and 5k on certain vw, toy, lexus, saab models


Wow I did not know the "Magnum" engines were sludge prone...I knew all the newer 2.7, 3.7, & 4.7 were marked as sludge monsters, but I did not know the older push rod engines were? Are you sure?

If that is the case, then maybe I did good by doing 3k OCI on my 5.9 with M1 regardless of being told I was wasting my money.

I also was aware the Camry 4cyl in some years were marked. VERY interesting that Amsoil had the presence of mind to issue a TSB - good for them for being on top of things when so many others are not.
 
great to hear amsoil notified user about sludge engines anddoing 3000 oci. now that is company on the ball.or should i say they are really thinking with their dipstick....
 
That's a trickier question than it appears. The pivot point is what do we mean by "bad". May sound simple, but it's really not, at least in this context. Is "bad" a spec-oil that has a skimpy add pack? Is bad a true non-spec oil like an SA used in an SM car? I think we could probably all agree that would be bad...

My opinion is that for "normal" contemporary vehicles, if it meets the SM standard, it's serviceable (good or bad up to you...). If you have a car that needs a strong EP and/or AW additives (like everyone's favorite ZDDP), things get trickier. And so on.

Need a better definition of "bad".
 
Originally Posted By: ekpolk
That's a trickier question than it appears. The pivot point is what do we mean by "bad". May sound simple, but it's really not, at least in this context. Is "bad" a spec-oil that has a skimpy add pack? Is bad a true non-spec oil like an SA used in an SM car? I think we could probably all agree that would be bad...

My opinion is that for "normal" contemporary vehicles, if it meets the SM standard, it's serviceable (good or bad up to you...). If you have a car that needs a strong EP and/or AW additives (like everyone's favorite ZDDP), things get trickier. And so on.

Need a better definition of "bad".


If you did an oil test and took say 10 different dino oils of the same weight and ran them in a chevy 350 changed every 3-5k for 250k miles for the same operating conditions and then disassymbled the motors and compared the wear, cleanliness, etc. Then would their be one oil that SUBSATNTIALLY stood out as the poorest performer with no debate about it. And then it could be said that all the other oils did a "good" job protecting the motor but OIL #10 is a "bad" oil and don't use that in your car.

does that help a little?
 
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Originally Posted By: FastSUV
Originally Posted By: ekpolk
That's a trickier question than it appears. The pivot point is what do we mean by "bad". May sound simple, but it's really not, at least in this context. Is "bad" a spec-oil that has a skimpy add pack? Is bad a true non-spec oil like an SA used in an SM car? I think we could probably all agree that would be bad...

My opinion is that for "normal" contemporary vehicles, if it meets the SM standard, it's serviceable (good or bad up to you...). If you have a car that needs a strong EP and/or AW additives (like everyone's favorite ZDDP), things get trickier. And so on.

Need a better definition of "bad".


If you did an oil test and took say 10 different dino oils of the same weight and ran them in a chevy 350 changed every 3-5k for 250k miles for the same operating conditions and then disassymbled the motors and compared the wear, cleanliness, etc. Then would their be one oil that SUBSATNTIALLY stood out as the poorest performer with no debate about it. And then it could be said that all the other oils did a "good" job protecting the motor but OIL #10 is a "bad" oil and don't use that in your car.

does that help a little?


No, unfortunately not very much. The point I'm trying to make is that, while there certainly will be variation in performance between different oils, it's still very hard to isolate what such variation means. For example, if the test engine you choose to use is a flat tappet design, as it appears you've chosen, then among the many variables in oil performance, perhaps the characteristics of the EP and AW additives become the critical controlling factors. If you choose another engine for your test, say an early Toyota 1MZ V-6 that had the unfortunate habit of roasting its oil to death, but no EP issues in the valvetrain, then perhaps heat tolerance or oxidation performance becomes the critical variable that will define what's good and what's "bad".

I'm not simply "playing dumb" on this question. I'm just trying to point out that when you're looking at a product like motor oil, that may vary from a similar product in dozens of different ways, using overbroad labels like "good" and "bad" doesn't help much, unless we do more to define what we mean by good or bad, for a given situation.

Ironically, the standards (SAE, ILSAC, etc), which have been so helpful and positive overall, may actually help to mask and obscure real differences between lube products. For most apps, you can safely grab whatever oil carries the right approvals. Hey, if it says SM, and your car calls for it, you're very probably totally safe grabbing any SM that suits you. But if you want to parse it out more, you'll have to dig deeper to find the individual data points about the oil that you find important for your application.
 
Quote:
Ironically, the standards (SAE, ILSAC, etc), which have been so helpful and positive overall, may actually help to mask and obscure real differences between lube products


Yes. Many tests are PASS:FAIL ..and some oils PASS better than others.

Use their oil and the rewards would be ....

How much?

..Well, more than you can imagine.

I don't know, kid. I can imagine quite a bit.
 
I would say there is no Bad oil provided it is the correct weight, meets your engine specification and is changed at the OEM's recommended OCI or something other OCI that is reasonable for the oils composition and your driving conditions.

With that being said. Even Synlube is a good oil, I just think their "Life-Time" fill is a bit of nonsense but they do claim that they have proof running it in a Kia engine for something like 200K miles with only top-off's.
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Originally Posted By: tomcat27
now, there certainly are some bad engines!
In fact, Amsoil issues a TSB recommending short OCI's on certain "sludge" engines. on my DC 2.7 Amsoil recommends 3k miles! also on the dodge 3.9, 5.2, 5.9 and 5k on certain vw, toy, lexus, saab models

Do you know if they have these on their website? I'd imagine my 350 is considered a sludger with all the fuel dilution.
 
Originally Posted By: 72customdeluxe
Originally Posted By: tomcat27
now, there certainly are some bad engines!
In fact, Amsoil issues a TSB recommending short OCI's on certain "sludge" engines. on my DC 2.7 Amsoil recommends 3k miles! also on the dodge 3.9, 5.2, 5.9 and 5k on certain vw, toy, lexus, saab models

Do you know if they have these on their website? I'd imagine my 350 is considered a sludger with all the fuel dilution.


nah 350 is one of the most reliable engines ever made as long as it can breathe; be sure PCV is good...and also, not all 350's were flat tappet so that is subjective in my choice of test motor, but either way, whether is was a '96 vortec or a '85 flat tappet design I just would want to use the same motor to test all the oils.

It could be a Nissan Z24 4cyl...doesn't matter, just a proven engine without a "known" reputation for anything extra like being prone to "cooking" its oil or sludge.
 
Originally Posted By: FastSUV

Wow I did not know the "Magnum" engines were sludge prone...I knew all the newer 2.7, 3.7, & 4.7 were marked as sludge monsters, but I did not know the older push rod engines were? Are you sure?

The 2.7L yes, proven. The 3.7L and 4.7L... interesting. I wouldn't post that on JU. You know that Carlito Benito guy would certainly give you a hard time....
grin2.gif
 
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Originally Posted By: JeepZJ4.0
Originally Posted By: FastSUV

Wow I did not know the "Magnum" engines were sludge prone...I knew all the newer 2.7, 3.7, & 4.7 were marked as sludge monsters, but I did not know the older push rod engines were? Are you sure?

The 2.7L yes, proven. The 3.7L and 4.7L... interesting. I wouldn't post that on JU. You know that Carlito Benito guy would certainly give you a hard time....
grin2.gif



If I recall, he is from "Texas" too is he not...hmmm

Anyway, it is documented the 4.7 is a sludger and that is why they came out with the half-hearted TSB fix that really does not fix the issue.

It is more seen in 4.7's that do FST's and are where it is colder outside though. I have heard there is a hack that can be done with a Chevy PCV that resolves the problem, but again, if someone has a 4.7 and uses 5w30 and chnages it by 3-4k then most likely they would be okay unless conditions above. It was apoor engine design to cause that problem.
 
A bad oil is the oil that is in the crank when the engine blows. Doesn't matter how long its been in the crank, how many miles, or how low on the stick it is. It's the fact that it was the last oil that entered the engine, that's what makes it a bad oil.
 
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