So dramatic
Pep Boys warns Not to mix oils.
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Originally Posted By: Danh
while the the resulting viscosity is predictable,
Don't think it is, at least not very precisely.
In practice, IIRC the viscosity of mixed multigrades can only be determined empirically, by experiment, so unless you have some data on that particular mix, you're experimenting.
It'll probably be OK though.
while the the resulting viscosity is predictable,
Don't think it is, at least not very precisely.
In practice, IIRC the viscosity of mixed multigrades can only be determined empirically, by experiment, so unless you have some data on that particular mix, you're experimenting.
It'll probably be OK though.
I mix leftover oils all the time.No big deal
61,000 miles. BUT battery life is more dependent on age than miles, as repeated hot summers dry out the cells. They usually start dying after 10 years.
Also the pack becomes "unbalanced" the more it is used, with some cells holding 1.2 volts and others holding 1.0. Then the "check battery" light comes on, and the dealer tells you to buy a new one. (Or you can let it sit for a month, and hope the CBL goes away when the battery self-discharges to empty.... i.e. rebalanced.)
Remanned batteries don't last more than 2 years according to hybrid owners that tried them. They are made from 2-3 old packs merged into 1 remanned pack, which means you still are running 10+ year old cells. Plus they don't save much money: $2500 versus $1500.
Also the pack becomes "unbalanced" the more it is used, with some cells holding 1.2 volts and others holding 1.0. Then the "check battery" light comes on, and the dealer tells you to buy a new one. (Or you can let it sit for a month, and hope the CBL goes away when the battery self-discharges to empty.... i.e. rebalanced.)
Remanned batteries don't last more than 2 years according to hybrid owners that tried them. They are made from 2-3 old packs merged into 1 remanned pack, which means you still are running 10+ year old cells. Plus they don't save much money: $2500 versus $1500.
I can't remember anyone having an oil related problem regardless of what oil they used.
I have mixed for years and I know of others who do the same.
There is no combination of different brands that will do damage.
Some folks here worry too much.
I have mixed for years and I know of others who do the same.
There is no combination of different brands that will do damage.
Some folks here worry too much.
Originally Posted By: Dallas69
I can't remember anyone having an oil related problem regardless of what oil they used.
I have mixed for years and I know of others who do the same.
There is no combination of different brands that will do damage.
Some folks here worry too much.
Like I said, I like keeping my oil the same but I always consider mismatched oil to be better than low oil. I'll even toss in the wrong viscosity if I need oil and can't find what I need.
Going back to my favorite oil [censored] the MG, I was once out on a drive and didn't realize that I had a kind of bad oil leak(worse than usual, albeit mine really leaks very little oil). I pulled into a gas station to get gas then noticed the leak, and fortunately was able to fix it. I only had one quart with me and I was down two quarts or so. I went into the station, and the best I could do was their house brand 10W-40. Again, any oil is better than none, so I bought that $7 quart of oil and dumped it in. My oil pressure did drop a bit, but not enough to concern me(probably 2-3 psi).
I can't remember anyone having an oil related problem regardless of what oil they used.
I have mixed for years and I know of others who do the same.
There is no combination of different brands that will do damage.
Some folks here worry too much.
Like I said, I like keeping my oil the same but I always consider mismatched oil to be better than low oil. I'll even toss in the wrong viscosity if I need oil and can't find what I need.
Going back to my favorite oil [censored] the MG, I was once out on a drive and didn't realize that I had a kind of bad oil leak(worse than usual, albeit mine really leaks very little oil). I pulled into a gas station to get gas then noticed the leak, and fortunately was able to fix it. I only had one quart with me and I was down two quarts or so. I went into the station, and the best I could do was their house brand 10W-40. Again, any oil is better than none, so I bought that $7 quart of oil and dumped it in. My oil pressure did drop a bit, but not enough to concern me(probably 2-3 psi).
About .5 to 1.5 quarts remain in the engine after an oil change. If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
Originally Posted By: dave1251
About .5 to 1.5 quarts remain in the engine after an oil change. If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
That's a strawman argument..."mixing" and "done for" aren't what is typically claimed for the reasons not to do it.
Vast majority of people don't use the absolute limits of their oil's performance, and lack of harm isn't proof of benefit.
If you absolutely need a 0W something oil due to location and ambient, then mixing different 0W brands is dicing with "nothing bad happening", as that's the point in their performance curve that is most likely to be impacted by mixing.
And there are SAE papers where the wrong combination of variables led to oils that were near solid at room temperature...unlikely, very unlikely, but if you need 0W for your environment, then don't mix.
About .5 to 1.5 quarts remain in the engine after an oil change. If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
That's a strawman argument..."mixing" and "done for" aren't what is typically claimed for the reasons not to do it.
Vast majority of people don't use the absolute limits of their oil's performance, and lack of harm isn't proof of benefit.
If you absolutely need a 0W something oil due to location and ambient, then mixing different 0W brands is dicing with "nothing bad happening", as that's the point in their performance curve that is most likely to be impacted by mixing.
And there are SAE papers where the wrong combination of variables led to oils that were near solid at room temperature...unlikely, very unlikely, but if you need 0W for your environment, then don't mix.
Originally Posted By: Shannow
Originally Posted By: askani79705
I mix leftover oils all the time.No big deal
Yep, the new BITOG performance standard is "nothing broke"...It's much simpler than the suite of tests specced by the API, ACEA, and SAE.
Good one!
Originally Posted By: askani79705
I mix leftover oils all the time.No big deal
Yep, the new BITOG performance standard is "nothing broke"...It's much simpler than the suite of tests specced by the API, ACEA, and SAE.
Good one!
Originally Posted By: dave1251
If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
That's why you have to buy in bulk quantities like me, so several oil changes all have the same batch number.
Heck, I used to do that buying at Walmart, even, a box of 5 quart jugs at a time.
If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
That's why you have to buy in bulk quantities like me, so several oil changes all have the same batch number.
Originally Posted By: dave1251
About .5 to 1.5 quarts remain in the engine after an oil change. If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
Agreed. I know my engine has 5L of oil in it when rebuilt. It says so in the manual - 5L dry engine, 4L oil change with filter, 3.8 without filter change. I always change oil too early so there would be 1L of additive laden oil remaining in the engine every time.
I can't believe this has not been debunked and people still think it's an issue. Even after all the VOA and used oil analysis here of mixed oils AND the complete and lack of engine death due to mixing. I agree with Shannow too though, in that you wouldn't mix if requiring some particular oil specifications due to engine type (low saps/dpf etc) or climate.
But I fully intend on mixing a free 20L container of 15W40 with 5L of 5W20 to thin things out a little in my high mileage, 11 year old Toyota for some short 5,000 km changes.
About .5 to 1.5 quarts remain in the engine after an oil change. If mixing is a serious issue we are all done for. Factor even the same brands change formulations every few years, batch variations, and then the people who jump brands each OCI. All of our engines are done within the next year.
Agreed. I know my engine has 5L of oil in it when rebuilt. It says so in the manual - 5L dry engine, 4L oil change with filter, 3.8 without filter change. I always change oil too early so there would be 1L of additive laden oil remaining in the engine every time.
I can't believe this has not been debunked and people still think it's an issue. Even after all the VOA and used oil analysis here of mixed oils AND the complete and lack of engine death due to mixing. I agree with Shannow too though, in that you wouldn't mix if requiring some particular oil specifications due to engine type (low saps/dpf etc) or climate.
But I fully intend on mixing a free 20L container of 15W40 with 5L of 5W20 to thin things out a little in my high mileage, 11 year old Toyota for some short 5,000 km changes.
Originally Posted By: Dallas69
I can't remember anyone having an oil related problem regardless of what oil they used.
I have mixed for years and I know of others who do the same.
There is no combination of different brands that will do damage.
Some folks here worry too much.
Yes!
I can't remember anyone having an oil related problem regardless of what oil they used.
I have mixed for years and I know of others who do the same.
There is no combination of different brands that will do damage.
Some folks here worry too much.
Yes!
The manager might have been OCD about oil, but coming to BITOG to diagnose oil OCD is a bit like going to the asylum, as it were.
my work car (2005 sunfire 2.2L) gets whatever is left over... couple bottles of supertech, bottle of quaker state, bottle of synthetic...etc... i try to keep them all 5-30 but if i'm a quart shy i'll throw some 10-30 i keep for my dads truck when i change his oil in there. that car has never seen a straight oil change, usually whatever i have in my cabinet from other oil changes.
runs smooth. runs good. runs fine. no issues.
runs smooth. runs good. runs fine. no issues.
Originally Posted By: sh40674
my work car (2005 sunfire 2.2L) gets whatever is left over... couple bottles of supertech, bottle of quaker state, bottle of synthetic...etc... i try to keep them all 5-30 but if i'm a quart shy i'll throw some 10-30 i keep for my dads truck when i change his oil in there. that car has never seen a straight oil change, usually whatever i have in my cabinet from other oil changes.
runs smooth. runs good. runs fine. no issues.
Yea- but respectfully that car is worth $2,000.00 dollars. I find it hard to believe you would do that in a $20,000.00 car.......
my work car (2005 sunfire 2.2L) gets whatever is left over... couple bottles of supertech, bottle of quaker state, bottle of synthetic...etc... i try to keep them all 5-30 but if i'm a quart shy i'll throw some 10-30 i keep for my dads truck when i change his oil in there. that car has never seen a straight oil change, usually whatever i have in my cabinet from other oil changes.
runs smooth. runs good. runs fine. no issues.
Yea- but respectfully that car is worth $2,000.00 dollars. I find it hard to believe you would do that in a $20,000.00 car.......
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