Mixing Rotella 15w40 with Delvac 15w40
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No problem. These 2 oils are very simmilar.
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Originally Posted By: Chris142
No problem. These 2 oils are very simmilar.
That's a pretty bold statement. These two oils are aimed at similar MARKETS. That's quite a ways from being "similar" in makeup. Will you get concrete? NO. Will you get a mixture that is within 75% of the performance of either oil by itself? Probably not.
If you do mix, don't run it for a long OCI. Better to leave the extra qt for a time when you have a k left to go and need a top off.
No problem. These 2 oils are very simmilar.
That's a pretty bold statement. These two oils are aimed at similar MARKETS. That's quite a ways from being "similar" in makeup. Will you get concrete? NO. Will you get a mixture that is within 75% of the performance of either oil by itself? Probably not.
If you do mix, don't run it for a long OCI. Better to leave the extra qt for a time when you have a k left to go and need a top off.
Originally Posted By: Lurch
I hope this isn't a dumb question.
Nope, this is the oil forum. The only dumb one is the one you didn't ask.
I hope this isn't a dumb question.
Nope, this is the oil forum. The only dumb one is the one you didn't ask.
I mix and match these two oils all the time...mainly because I have both in my garage. They go into my motorcycle and cars, except for my NSX...mainly because I feel it doesn't need it for the kind of driving I do with that car.
They are similar in makeup. We have analyzed both in our labs at work. Remember, there are only a certain number of compounds (amines and ethers for example) that will do what is required for an engine oil. All the fancy names for additive packages are more marketing for each company. For example, PTFE is marketed as Teflon by Dupont. But there are plenty of nonsticks that are PTFE (because PTFE is the only compound that does what it does), just not marketed as Teflon.
They are similar in makeup. We have analyzed both in our labs at work. Remember, there are only a certain number of compounds (amines and ethers for example) that will do what is required for an engine oil. All the fancy names for additive packages are more marketing for each company. For example, PTFE is marketed as Teflon by Dupont. But there are plenty of nonsticks that are PTFE (because PTFE is the only compound that does what it does), just not marketed as Teflon.
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If you do mix, don't run it for a long OCI. Better to leave the extra qt for a time when you have a k left to go and need a top off.
Then maybe I should not mix them, because I plan to run oils in both vehicles for a year from the next OCI (4/1 is going to be my annual OCI time for both my car and motorcycle from now on). I want to make sure I use oils that are plenty good enough to last a year : Rotella T6 Synthetic 5w40 in the car and Delvac 15w40 in the bike.
If you do mix, don't run it for a long OCI. Better to leave the extra qt for a time when you have a k left to go and need a top off.
Then maybe I should not mix them, because I plan to run oils in both vehicles for a year from the next OCI (4/1 is going to be my annual OCI time for both my car and motorcycle from now on). I want to make sure I use oils that are plenty good enough to last a year : Rotella T6 Synthetic 5w40 in the car and Delvac 15w40 in the bike.
I've got a 30+ year old Tecumseh engine on Craftsman lawn mower. That engine has seen all sorts of left over oil concoctions over the years and still runs like a charm.
I also have a 29 year old Kubota diesel power plant the get's similar treatment. Never had a problem with it either and it's got something like 6000 hours on it.
As previously mentioned, we often obsess over stuff that is simply insignificant.
I also have a 29 year old Kubota diesel power plant the get's similar treatment. Never had a problem with it either and it's got something like 6000 hours on it.
As previously mentioned, we often obsess over stuff that is simply insignificant.
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I've got a 30+ year old Tecumseh engine on Craftsman lawn mower. That engine has seen all sorts of left over oil concoctions over the years and still runs like a charm.
That's probably because you always paid attention to the oil level regardless of the brand of oil, something that not all people do.
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As previously mentioned, we often obsess over stuff that is simply insignificant.
I'm going to add that quart of Rotella 15w40 to 2 quarts of Delvac and run it in the bike, and I'd bet $5 it will hold up well and keep that motor happy for quite a while.
I've got a 30+ year old Tecumseh engine on Craftsman lawn mower. That engine has seen all sorts of left over oil concoctions over the years and still runs like a charm.
That's probably because you always paid attention to the oil level regardless of the brand of oil, something that not all people do.
Quote:
As previously mentioned, we often obsess over stuff that is simply insignificant.
I'm going to add that quart of Rotella 15w40 to 2 quarts of Delvac and run it in the bike, and I'd bet $5 it will hold up well and keep that motor happy for quite a while.
Originally Posted By: dtt004
I mix and match these two oils all the time...mainly because I have both in my garage. They go into my motorcycle and cars, except for my NSX...mainly because I feel it doesn't need it for the kind of driving I do with that car.
They are similar in makeup. We have analyzed both in our labs at work. Remember, there are only a certain number of compounds (amines and ethers for example) that will do what is required for an engine oil. All the fancy names for additive packages are more marketing for each company. For example, PTFE is marketed as Teflon by Dupont. But there are plenty of nonsticks that are PTFE (because PTFE is the only compound that does what it does), just not marketed as Teflon.
I seriously question this take on oil.
To give one example. A small level of the additive ZDDP + Boron gives better performance than a larger level of either just ZDDP or ZDDP + Boron. So, one oil uses ZDDP+Boron, and one uses just ZDDP at a higher concentration. Mix the two and the resultant oil has too much ZDDP for the synergistic function, and not enough to match the high ZDDP oil in functionality.
Concrete? NO. A mix as good as either oil by itself? notsomuch...
I mix and match these two oils all the time...mainly because I have both in my garage. They go into my motorcycle and cars, except for my NSX...mainly because I feel it doesn't need it for the kind of driving I do with that car.
They are similar in makeup. We have analyzed both in our labs at work. Remember, there are only a certain number of compounds (amines and ethers for example) that will do what is required for an engine oil. All the fancy names for additive packages are more marketing for each company. For example, PTFE is marketed as Teflon by Dupont. But there are plenty of nonsticks that are PTFE (because PTFE is the only compound that does what it does), just not marketed as Teflon.
I seriously question this take on oil.
To give one example. A small level of the additive ZDDP + Boron gives better performance than a larger level of either just ZDDP or ZDDP + Boron. So, one oil uses ZDDP+Boron, and one uses just ZDDP at a higher concentration. Mix the two and the resultant oil has too much ZDDP for the synergistic function, and not enough to match the high ZDDP oil in functionality.
Concrete? NO. A mix as good as either oil by itself? notsomuch...
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Originally Posted By: boraticus
I've got a 30+ year old Tecumseh engine on Craftsman lawn mower. That engine has seen all sorts of left over oil concoctions over the years and still runs like a charm.
I also have a 29 year old Kubota diesel power plant the get's similar treatment. Never had a problem with it either and it's got something like 6000 hours on it.
As previously mentioned, we often obsess over stuff that is simply insignificant.
As with most anecdotal experience, this only proves that your engines didn't explode. Did the mixes do better than a single oil? You can't say (even with UOA, although multiple UOA with mixes vs singles would help), and neither can I.
Using this as "proof" however is silly.
I've got a 30+ year old Tecumseh engine on Craftsman lawn mower. That engine has seen all sorts of left over oil concoctions over the years and still runs like a charm.
I also have a 29 year old Kubota diesel power plant the get's similar treatment. Never had a problem with it either and it's got something like 6000 hours on it.
As previously mentioned, we often obsess over stuff that is simply insignificant.
As with most anecdotal experience, this only proves that your engines didn't explode. Did the mixes do better than a single oil? You can't say (even with UOA, although multiple UOA with mixes vs singles would help), and neither can I.
Using this as "proof" however is silly.
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A mix as good as either oil by itself? notsomuch...
Yeah, but we're cutting hairs here. If it sounds good, feels good, runs good, looks good, chances are it's doing a wonderful job of lubricating my engine. I will trust my common sense on that.
A mix as good as either oil by itself? notsomuch...
Yeah, but we're cutting hairs here. If it sounds good, feels good, runs good, looks good, chances are it's doing a wonderful job of lubricating my engine. I will trust my common sense on that.
"As with most anecdotal experience, this only proves that your engines didn't explode."
Yeah.... no explosions or failure, in what???? 30 years.....
I must be flirting with disaster, that's for sure.
I bet I don't get 60 years out of them!
DARN!!!!
Yeah.... no explosions or failure, in what???? 30 years.....
I must be flirting with disaster, that's for sure.
I bet I don't get 60 years out of them!
DARN!!!!
Originally Posted By: Lurch
Yeah, but we're cutting hairs here. ....
It's what we do.
Yeah, but we're cutting hairs here. ....
It's what we do.
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