MIxing Oils

CCI

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Is there any problem with mixing 20w-50 oil from different manufacturers? What about mixing different viscosity? Like mixing 15-40 with 20w-50 or mixing a multi-viscosity oil with a straight-weight?
 
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usually there is no problem. many of us mix oils all the time, and so far so good. the end result is an oil with an inbetween viscosity, in between what u started with.
 

CCI

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Thanks! While I'm sure the oil companies don't want us playing Junior Chemist, it's something I've always wondered about. I usually run 20w-50 in the winter and straight SAE 50 or if it's really hot SAE 60 in my old Harley. But sometimes there isn't much choice, it's about whatever is available.
 
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Last OCI in my 08 Focus I ran 3 qts Napa Syn 5w20, 1/2 qt PP 5w20, 1/2 qt Valvoline Conventional 5w30 and 1/2 qt Valvoline Conventional 5w20. The car had only 15000 miles on it when I installed this oil. Hey were in an economic slump...why should I buy more oil and let good oil sit on my shelf for years and never get used. It was new oil. I just knew that if I didn't use it, it would sit there for years.
 
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I mix all the time. A while back before I got some new additions to the stash, I think there was like 5 different brands in the sump (including top ups though) and the engine ran fine. Mind you, i was not putting in used oil, or bottom quality. It was all Castrol/FormulaShell, Esso, Pennzoil. LOL.
 
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6 different oils, 5 different brands, and 3 different weights in my moms car right now. It's 3,000 miles in and nothing seems any different than when it ran straight brands and weights previously. Mobil 1 10W-30 Extended Performance Mobil 1 10W-30 Valvoline Synpower 5W-30 Super Tech 5W-30 synthetic Quaker State Torque Power 5W-30 synthetic Motorcraft 5W-20 synthetic blend
 
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You runnin' an ol pan head or is this a shovel or block head? ... either way, the bike will run fine as long as it's not too thick and it'll probably kick over a little easier with a little of the "thin" stuff mixed in. I've got 15w40 in my block head right now (along with some ARX) and it's purrin' right along. If you're running a 15w40, you can always drop a bottle of STP in for some more viscosity if you hit those 100+ days ... any mix of them should work well as long as it's changed regularly ... ride safe.
 

CCI

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'77 Shovel, no idea how many miles, on its second set of cylinders, third set of heads, probably 6 or 7 cams, second set of gears in the tranny, second bottom end so far so good knock on wood. I wondered about this because Chevron Delo 400 SAE 50 straight weight gets a great ring seal but I'm not so sure about the cam rollers holding up with it. Thinking about mixing Delo SAE 50 with some 20w-50 Kendall or Castrol GTX.
 
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 Originally Posted By: Camu Mahubah
Last OCI in my 08 Focus I ran 3 qts Napa Syn 5w20, 1/2 qt PP 5w20, 1/2 qt Valvoline Conventional 5w30 and 1/2 qt Valvoline Conventional 5w20. The car had only 15000 miles on it when I installed this oil. Hey were in an economic slump...why should I buy more oil and let good oil sit on my shelf for years and never get used. It was new oil. I just knew that if I didn't use it, it would sit there for years.
I did something along those lines, to get rid of some straggler quarts of oil. So far so good. AD
 
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I think that I have chimed in on just about every thread asking about mixing oil brands/grades/weights. I've been mixing for over 35 years and never a problem. I usually keep my vehicles into their teens with several hundred thousand miles on them. Back then it was due to lack of money or I was just looking for cheap oil for a beater. My most famous mixes were when I used 5 different brands of oil, each brand being a different grade/weight... Engine ran fine! Today, I have so many different "name" brands/weights/grades of oil in my stash,(all oils are held in high regard here at BITOG) that I have purchaced on sale/rebate/closeout. The oils that I mix today consist of some Syn with dino and/or some 5W20 w/5W30 especially in the winter. In the summer, I may use some 10W30 w/5W30...It all depends on what I have in my stash at that time. My stash consist of(DINO-GTX, PYB, Valv, Hav, Chev, Peak) & (SYN- PP, M-1, QS/TP, ValvDB). All good stuff today!
 
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I was a brand loyal, a never mix oils kind of guy until I joined BITOG. I knew mixing oils was OK, I just wouldn't do it. Now I have no problem doing it in my 93 Aerostar, especially to get rid of widow and orphan quarts of oil. Nothing bad is going to happen. If fact I like the idea of mixing dino with synthetic, or 5W20 with 5W30 to make a blend of my own. I won't mix oils in my new Jeep or my E-150, but when they become beaters, anything goes. Sometimes my OCD is too strong and won't allow me to do certain things. LOL
 
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I've mixed for years, getting rid of odd ball quarts of oil too when I had too. I've never noticed any difference between the two (mix vs straight). I just changed the oil on my 530i BMW and in went 4 quarts of M1 0w40 and 3 quarts of 10w30 Amsoil. Car is running great. Both are great oils, but I didn't have 7 quarts of each, so I mixed em. The wife's SRX is running 5 quarts of GC 0w30 and 1 quart of 5w20 Castrol Synthetic. It's never run so good!
 
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While I would say there's usually no problem with mixing, you don't always know what you're going to end up with. I've mixed plenty of times. But I don't know if I would mix different brands with different addy packs with the belief that I've come up with something fundamentally better.
 
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Yep, I'd want some flow...just runnin' 20w50 or a mix that about equals that should keep enough flow and have enough viscosity too ...
 
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 Originally Posted By: HTSS_TR
If you have a nice car such as a Ferrari or a Porsche, would you mix various brands and weights ?
Not by design. But if I had appropriate synthetic weights refined by different manufacturers on hand, sure. I wouldn't have a problem mixing a quart or two of brand x with brand y... I would try to keep spec's together though, such as SL, SM, ACEA A3, etc...
 
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