Would it be O.K. if I mixed 3 quarts of Castrol Syntec 5w-20 with 3 quarts of Castrol GTX 5w-20? Could this cause any lubrication problems?
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Could this oil blend damage my engine?
- Thread starter RTBandit
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no
This will be a synthetic blend with much more synthetic than 6 quarts of any synthetic blend oil, at probably about the same total price or cheaper. Go for it.
For what it's worth, Castrol says all their oils are compatible. I stocked up on Syntec blend due to the recent fire sale ($1.50) at Wal-Mart and usually use their high mileage, so I called the 800 number and asked.
RTBandit
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Thanx guys - I appreciate all the help.
Originally Posted By: rg200amp
..... I would not make it a habit, but no worries!
Why do you say that?
..... I would not make it a habit, but no worries!
Why do you say that?
Bill mixed a bunch of half and quarter bottles, quarts, that is, that he had lying around for many months if not years. Some dino, a couple or three brands, some syn, some of this, some of that.. Ran the stuff 4 or 5K and did a UOA, got the best UOA he ever got on, I believe, a Corolla or some such. BILL! Help me out here, am I remembering the car right? This was 3 or 4 or 5 years back. HE may not remember, but *I* do!
Point of the exercise was that, there is no point. All these oils are so good, the engines so clean, the fuel control so tight, the ventilation of the crankcase so thorough, that once you get into the realm of SL/SM-GF4, it's all oranges. Or apples. Now stop worrying! USE WITH CONFIDENCE!!!
Point of the exercise was that, there is no point. All these oils are so good, the engines so clean, the fuel control so tight, the ventilation of the crankcase so thorough, that once you get into the realm of SL/SM-GF4, it's all oranges. Or apples. Now stop worrying! USE WITH CONFIDENCE!!!
Originally Posted By: rg200amp
IMHO, A oils chemistry works best when it is used solo, not diluted by another oils chemistry.
It will work fine. I would just not make it a habit, due to I feel a oil works best when its using its own chemistry.
Competing chemistry only becomes a problem if you are running oils from vastly differing base stocks like a Gp. II or Gp. II+ with a PAO and even then it's not really a serious issue as long as the oils conform to the same standard and weight. This is why synthetic blends from similar stock are perfectly fine. What the OP has done here is pretty much make his own homebrew Castrol Syntec Blend, only his brew has probably 1/3 to 1/2 more Syntec in it!
IMHO, A oils chemistry works best when it is used solo, not diluted by another oils chemistry.
It will work fine. I would just not make it a habit, due to I feel a oil works best when its using its own chemistry.
Competing chemistry only becomes a problem if you are running oils from vastly differing base stocks like a Gp. II or Gp. II+ with a PAO and even then it's not really a serious issue as long as the oils conform to the same standard and weight. This is why synthetic blends from similar stock are perfectly fine. What the OP has done here is pretty much make his own homebrew Castrol Syntec Blend, only his brew has probably 1/3 to 1/2 more Syntec in it!
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We mix Shaeffers Series 7000 10-30 with Shaeffers Series 7000 20-50 and have outstanding UOA's and perfect oil pressure etc.
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A strange combination that seemed to make my car run reallyyyyyyy smooth was one time I did an oil change,and I used 4 quarts M1 15W50 sc,and a half quart RP 15W40 (was trying to use up leftover oils).
Ran smooth as silk!
Ran smooth as silk!
Originally Posted By: Peter_Pan
Originally Posted By: rg200amp
IMHO, A oils chemistry works best when it is used solo, not diluted by another oils chemistry.
It will work fine. I would just not make it a habit, due to I feel a oil works best when its using its own chemistry.
Competing chemistry only becomes a problem if you are running oils from vastly differing base stocks like a Gp. II or Gp. II+ with a PAO and even then it's not really a serious issue as long as the oils conform to the same standard and weight. This is why synthetic blends from similar stock are perfectly fine. What the OP has done here is pretty much make his own homebrew Castrol Syntec Blend, only his brew has probably 1/3 to 1/2 more Syntec in it!
It will work fine. I am not really talking about "competing chemistry".
I feel these Oil companies spend a lot of money on research+development on makeing there oils. There detergents, antiwear additives, anti-foaming adds, base stock, ect. . . are blended to what they feel works best for the oil in that price range.
Theres no need to mix oils unless your just getting rid of old oil. Millions of dollars have been spent on the development of motor oil. I see no need to put on a lab coat in the garage and start mixing your own brews.
Mixing oils will not hurt your engine, but to go out of ones way and buy oils to mix every OCI is, IMHO, a waste of quality R+D.
Again this is just my opinion.
Originally Posted By: rg200amp
IMHO, A oils chemistry works best when it is used solo, not diluted by another oils chemistry.
It will work fine. I would just not make it a habit, due to I feel a oil works best when its using its own chemistry.
Competing chemistry only becomes a problem if you are running oils from vastly differing base stocks like a Gp. II or Gp. II+ with a PAO and even then it's not really a serious issue as long as the oils conform to the same standard and weight. This is why synthetic blends from similar stock are perfectly fine. What the OP has done here is pretty much make his own homebrew Castrol Syntec Blend, only his brew has probably 1/3 to 1/2 more Syntec in it!
It will work fine. I am not really talking about "competing chemistry".
I feel these Oil companies spend a lot of money on research+development on makeing there oils. There detergents, antiwear additives, anti-foaming adds, base stock, ect. . . are blended to what they feel works best for the oil in that price range.
Theres no need to mix oils unless your just getting rid of old oil. Millions of dollars have been spent on the development of motor oil. I see no need to put on a lab coat in the garage and start mixing your own brews.
Mixing oils will not hurt your engine, but to go out of ones way and buy oils to mix every OCI is, IMHO, a waste of quality R+D.
Again this is just my opinion.
Look at the back of oil bottles-they say synthetics are compatible with dino oils. The only execption could possibly some exotic race oils.
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