Mix Oil Brands for Oil Change?

[Oily_hair]

Originally Posted By: Dallas69
I like many others here buy oil when I come across sales so I end up with odd numbers of qts so when I need oil I grab what I have-if I am out of the brand currently in the vehicle I use another
I certainly dont know more than the oil companies but when they say it's ok to mix,I agree


Do they say that it is ok to mix their product with any oil brand on the bottle or website? The closest I have come to that is they say it is compatible with all conventional and synthetic oils. However, it seems that they are talking about when you are switching from a conventional oil to synthetic or vice versa and not necessarily endorsing a direct mixture of any oil brands with equal part mixtures. In other words no need to flush the engine entirely when making the switch. I don't think you will get any oil company that will endorse mixing different oil brands together with their product as they are in the business to sell only their product. Maybe you may get an endorsement in mixing their synthetic brand with their conventional but not mix any other brand name with their product....any issues that may arise from that and you are screwed in all corners of warranty coverage....who do you blame at that point?

 

[Dallas69]

Both of my car and truck are out of any warranty so that is no concern
My take on what the oil companies say about mixing is that ,as an example,any SN oil can be mixed.
They don't say that it is of any benefit,just that it can be done and you will be ok.
Isn't that one of the requirements for API certification?

 

[Shannow]

Go back and read the links...they are miscible with 6 API reference oils...that's the sum total of compatible for the purposes of API certification.

And almost invariably, the oil companies state that mixing will degrade performance.

 

[Oily_hair]

Originally Posted By: Dallas69
Both of my car and truck are out of any warranty so that is no concern
My take on what the oil companies say about mixing is that ,as an example,any SN oil can be mixed.
They don't say that it is of any benefit,just that it can be done and you will be ok.
Isn't that one of the requirements for API certification?


That is not what I am reading....I think the compatibility is strictly to address the issue way back in the day when an engine flush was required if you wanted to convert to synthetic oil. Now days, with the new oils that is no longer required and eliminates the need of a flush as it is completely compatible with the residual oil left over in the engine. Synthetics and conventionals can be used interchangebly with each other without any hassles or flushes and eliminating the extra cost of preparing the engine for the new synthetic oil. At least that is what I am getting out of what they mean when the talk about compatibility....BTW you are out of warranty but plenty of other users are not so as mentioned they would never endorse mixing equal parts with different brands.

 

[Dallas69]

I would be very surprised if most people don't mix,whether it is topping off or whatever
On my old truck for example,it takes 6 qts so if I use 5 qt jug and another qt
Like I said earlier I always have 60 to 70 qts of various brands,so I just pick one to use.If I happen to have the same oil as the jug I will use it,if not then something else gets used.
I wont go buy a qt just to match the jug.
Anyway,that's what I have done for years with zero problem.
I still believe most guys mix.
Maybe they haven't come out of the closet yet.

 

[Oily_hair]

Originally Posted By: Dallas69
I would be very surprised if most people don't mix,whether it is topping off or whatever
On my old truck for example,it takes 6 qts so if I use 5 qt jug and another qt
Like I said earlier I always have 60 to 70 qts of various brands,so I just pick one to use.If I happen to have the same oil as the jug I will use it,if not then something else gets used.
I wont go buy a qt just to match the jug.
Anyway,that's what I have done for years with zero problem.
I still believe most guys mix.
Maybe they haven't come out of the closet yet.


LOL, closet mixer here and coming out of the closet!! I mixed two different oils in my latest oil change as like you, using up the remaining oil from my last OC & I needed little over a quart for this one. Two quarts of oil would have been more costly than cracking open the PYB jug that would satisfy this oil change and the next oil change to the last drop. Had I read this thread earlier I think I would have invested in the two quarts but at least the mixture are both from Shell oil so I don't expect any major harm.

 

[OVERKILL]

Originally Posted By: Dallas69
I would be very surprised if most people don't mix,whether it is topping off or whatever
On my old truck for example,it takes 6 qts so if I use 5 qt jug and another qt
Like I said earlier I always have 60 to 70 qts of various brands,so I just pick one to use.If I happen to have the same oil as the jug I will use it,if not then something else gets used.
I wont go buy a qt just to match the jug.
Anyway,that's what I have done for years with zero problem.
I still believe most guys mix.
Maybe they haven't come out of the closet yet.


Most people probably don't mix because most of them don't change their own oil, LOL!

Those that do usually adhere to a specific brand because "that's what dad used" or something along those lines.

There are those that, as you've noted, shop on price, so will have individual quantities of various products around the house, but these are also people changing their own oil so they are, by virtue of that fact alone, not most people.

And of note here is also the distinct difference between blending specific products together intentionally, at various concentrations creating your own "blend" and topping up 1/2L or 1L of oil on the road when you are checking it and discovering you are down. The level of dilution can be significantly different in that case.

As noted, the standard isn't about people mixing their own oils trying to make their own grades, it is about general compatibility between lubricants from various blenders that the product isn't going to turn into something dramatically worse than each of the constituents on their own.

That doesn't mean it maintains the same certifications and approvals or that various aspects of its performance may perhaps be negatively affected, simply that no major issues regarding compatibility are going to happen. That's all that is tested for.

 

[wemay]

Originally Posted By: OVERKILL


That doesn't mean it maintains the same certifications and approvals or that various aspects of its performance may perhaps be negatively affected, simply that no major issues regarding compatibility are going to happen. That's all that is tested for.


I do read that it states that but i also understand that It does not mean it doesn't maintain the same certifications and approvals because again, it hasn't been tested for it. *playing devil's advocate here*

 

[Shannow]

It COULD also be equivalent to the hinge lubricant on the Hubble telescope...

The base oil interchange guidelines, which some mixing proponents have wheeled out in favour of mixing, would require certain tests to be carried out before an oil company could claim that blend x meets SN.

So clearly the blend doesn't have the same certification as either of the originals, and it certainly doesn't have the manufacturer's approvals.

It's like the argument that TGMO COULD meet ford's specs because nobody has tested that it doesn't.

So it's silly to claim that because it's untested, we don't know that a blend of any two off

 

[Olas]

It's only on BITOG that we (try to) use the same oil consistently, OCI after OCI.

All the other cars on the planet which are NOT owned by BITOGers have different oil every single time it's changed..

Dealerships and private garages use bulk oil, which is whatever is available cheapest when they order xhundred gallons - safe to saY it won't be the same as the FF..
then you have jiffy lube and other bulk oil users, and the guy who does his own changes with whatever is on sale..

It won't cause any problems whatsoever, mix with confidence

 

[wemay]

Originally Posted By: Shannow
It COULD also be equivalent to the hinge lubricant on the Hubble telescope...


Sooo you're saying we have a chance...

 

[OVERKILL]

Originally Posted By: wemay
Originally Posted By: OVERKILL


That doesn't mean it maintains the same certifications and approvals or that various aspects of its performance may perhaps be negatively affected, simply that no major issues regarding compatibility are going to happen. That's all that is tested for.


I do read that it states that but i also understand that It does not mean it doesn't maintain the same certifications and approvals because again, it hasn't been tested for it. *playing devil's advocate here*

That's not really playing devil's advocate. I don't get to claim I may maintain the same certifications as my parents; that I have my PhD in a specific subject because they have them and I simply haven't been tested

Either you test the necessary protocols and receive approval or you don't. You don't get to claim them by proxy.

 

[OVERKILL]

Originally Posted By: Olas
It's only on BITOG that we (try to) use the same oil consistently, OCI after OCI.

All the other cars on the planet which are NOT owned by BITOGers have different oil every single time it's changed..

Dealerships and private garages use bulk oil, which is whatever is available cheapest when they order xhundred gallons - safe to saY it won't be the same as the FF..
then you have jiffy lube and other bulk oil users, and the guy who does his own changes with whatever is on sale..

It won't cause any problems whatsoever, mix with confidence

A small amount of residual oil from a previous OCI mixing with the current fill isn't the same as intentionally mixing products together in volume though. Which is what is being discussed here.

 

[Dallas69]

I wonder if anyone here is going to stop mixing based on what has been discussed here?
I know that I wont hesitate to mix if I need to but that's just me.
Just curious about other folks.

 

[fredfactory]

Mixing very, very rarely ever causes any obvious outward problems.
Yet how much of what goes on in an engine (too much wear, deposits, etc.) can you just not see? So don't mix.

 

[Dallas69]

Over the years I have torn down my engines and never had any sludge,deposits,unusual wear etc.
Engines are just happy to get fresh oil regularly.
I am not as ocd about mixing as some.
Mixed oil doesn't turn into molasses you know.

 

[Shannow]

Originally Posted By: Dallas69
Mixed oil doesn't turn into molasses you know.


It can, has, and has been documented in SAE papers.

Rare, but it CAN happen.

 

[Oily_hair]

Originally Posted By: Dallas69
I wonder if anyone here is going to stop mixing based on what has been discussed here?
I know that I wont hesitate to mix if I need to but that's just me.
Just curious about other folks.


I've only done it once but my mixing days are over.

 

[deven]

Originally Posted By: Shannow
Originally Posted By: Dallas69
Mixed oil doesn't turn into molasses you know.


It can, has, and has been documented in SAE papers.

Rare, but it CAN happen.

How recent was that SAE paper? Was this on conventional oil, synthetic oil or both? I think with the purity of todays SN rated oils, mixed oil turning into molasses fear is little to none.

 

[OVERKILL]

Originally Posted By: deven
Originally Posted By: Shannow
Originally Posted By: Dallas69
Mixed oil doesn't turn into molasses you know.


It can, has, and has been documented in SAE papers.

Rare, but it CAN happen.

How recent was that SAE paper? Was this on conventional oil, synthetic oil or both? I think with the purity of todays SN rated oils, mixed oil turning into molasses fear is little to none.


It isn't the "purity" of the oils, is the clash of additives packages and PPD's used in anything that isn't PAO that can result in the oil's cold temperature performance degrading when blended with another lubricant that may use a different suite of additives due to different composition.