Guest bang847 Posted October 15, 2002 Share Posted October 15, 2002 hey guys someone told me that if you mix bases of oils things get crusty... is this true? i cannnot afford synthetic motor oil anymore.... do i need to flush it with something to switch? Quote Link to comment Share on other sites More sharing options...
gene_w Posted October 15, 2002 Share Posted October 15, 2002 Depends on the oil. I'm not sure about the others, but I know that you can mix Amsoil with anything without consequence. It was designed to be perfectly compatible with standard oils. Gene Quote Link to comment Share on other sites More sharing options...
Sumo Posted October 15, 2002 Share Posted October 15, 2002 As far as i know you dont need to flush out anything. I personally just use Castrol 10-30 regular oil. And i assume that synthetic blends are 50/50 synthetic and regular oil so it should be fine. Quote Link to comment Share on other sites More sharing options...
RPMS Posted October 15, 2002 Share Posted October 15, 2002 I think you're safe, Bang. That might have been true years ago, but even back then I think it was BS to keep folks scared into paying $6.00 a quart for Mobil 1. I've done extensive research into oils for automotive and motorcycle use, and what I've found suggests that as long as you change them at 3,000 mile intervals there's really very little advantage to using synthetic oils in a street driven engine. Just be sure to use a name brand oil with the SAE stamp, and you should never have a problem. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 15, 2002 Share Posted October 15, 2002 I use Chevron Dello 400 30 wt. I gave up on multi grade oils wearing out faster with extra additives. My oil consumption declined with the use of the Dello 10 years ago. Since then,if I changed to another brand, the oil level would drop until the Dello 400 30 weight was back in the lubrication business. Quote Link to comment Share on other sites More sharing options...
Guest bang847 Posted October 15, 2002 Share Posted October 15, 2002 Always helpful... Thanks guys.... Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted October 15, 2002 Share Posted October 15, 2002 There is no problem with mixing synthetic and conventional motor oils of any viscosity or brand. BTW I am a Castrol service engineer. Quote Link to comment Share on other sites More sharing options...
Guest bang847 Posted October 15, 2002 Share Posted October 15, 2002 Originally posted by Greimann:There is no problem with mixing synthetic and conventional motor oils of any viscosity or brand. BTW I am a Castrol service engineer. wonder where are my rebates? Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted October 15, 2002 Share Posted October 15, 2002 Oh, I'm with the industrial products division, not commercial. Rebates are not my job man! Quote Link to comment Share on other sites More sharing options...
Oltmann Posted October 15, 2002 Share Posted October 15, 2002 Originally posted by Greimann:There is no problem with mixing synthetic and conventional motor oils of any viscosity or brand. BTW I am a Castrol service engineer. Do you consider Syntec to be a synthetic oil? Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted October 16, 2002 Share Posted October 16, 2002 Here's an interesting question to ponder - Mobil sued some companies that were calling their oils "synthetic" when in fact the oils were apparently blended to some extent - unlike Mobil 1. Mobil lost the lawsuit! Shortly afterwards Mobil "repackaged" and "improved" their oil. Anyone but me wonder if perhaps Mobil 1 isn't as pure synthetic as it was before? Seen this debated more than once recently Does Castrol blend their synthetic oils? I'm suspicious of Mobil right now but don't know for sure if they've done anything sneaky or not Blending a synthetic with a mineral based oil is supposed to be okay. Synthetic oils are supposed to have a much higher detergent action so it may clean the motor out more. Not a bad thing IMO but have a good filter on it... Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted October 16, 2002 Share Posted October 16, 2002 I know there has been a lot of controversy about the definition of synthetic and Castrol Syntec was right in the middle of that. My answer is, yes, Syntec is a synthetic. Here is why in an a nutshell: The base stock for conventional motor oils are refined from crude using traditional thermal distillation techniques. The oil molecule itself is basically the same as how nature built it when was created out of decaying vegetable matter (not dinosaurs!) many millennia ago. Further refining techniques remove undesirable components out of the base stock, but leave the basic molecule alone. Synthetic base oils are created by chemically combining compounds or chemically altering petroleum based oils to shape the molecule into one that has the desired properties. Different manufacturers use different techniques, but the end result is something that has been chemically designed and not left in its state as initially refined. Different paths to the same destination. Syntec is made from altered petroleum base stock and other brands use chemically combined products (that can trace their origin eventually back to petroleum). This is a way oversimplified explnation but hopefully it makes the issue a little clearer. I am NOT a chemist so I rely on what I have read about the subject through technical references. Quote Link to comment Share on other sites More sharing options...
Guest De Schmaydee Posted November 7, 2002 Share Posted November 7, 2002 i've always thought that synthetics would not increase its viscosity as much in winter (like when the cars been setting overnight...) ...it was higher detergent...and it wouldnt coke-up my turbo as easily (if i shut the car off too quickly after a hard run)....are these things true?...s Quote Link to comment Share on other sites More sharing options...
Mudge Posted November 7, 2002 Share Posted November 7, 2002 Go with semi synthetic, Quaker State if you can find it. In a test by Amsoil, QS semi-synthetic was about .5% worse in a wear test than Mobil1, hardly a difference at all. In specifications, all of Quaker States products are low ash, high flash, etc etc, whupping arse of other brands by a good margin for the price. Quote Link to comment Share on other sites More sharing options...
blueovalz Posted November 7, 2002 Share Posted November 7, 2002 I can't put my finger on it, but I recall a study in which "non-synthetic/synthetic" blends were tested with differing proportions of the two. It was found that a small (percentage wise) amount of the supposedly "pure" synthetic oil mixed with a larger amount non-synthetic provided a blend whose characteristics were heavily weighted toward a pure synthetic oil. The result's curve then flattened out as the ratio of the two became closer to 1:1 with almost no difference in the blend characteristics from this ratio on toward the 100% synthetic blend. Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted November 7, 2002 Share Posted November 7, 2002 Originally posted by De Schmaydee:i've always thought that synthetics would not increase its viscosity as much in winter (like when the cars been setting overnight...) ...it was higher detergent...and it wouldnt coke-up my turbo as easily (if i shut the car off too quickly after a hard run)....are these things true?...s All of that is true. For cold weather performance, synthetic oils have a lower pour point than conventional oils. The pour point is the lowest temperature that an oil will pour out of an open container, or esentially when oil becomes petroleum flavored Jello. This property is really important in arctic conditions. The other temperature property is that synthetics have a flatter viscosity index curve. This means as the temperature decreases, they thicken less, and as temperature increases they thin less than conventional oils. The detergent properties are better because there is more room in the blend for detergent additives. Since synthetic oils are "designer molecules" with built in viscosity performance, they do not require viscosity improvers as additives. This leaves more room in a given volume of oil for other additives such as detergent / dispersant, antiwear, and acid neutralizing. Detergent properties of an oil help break loose deposits and suspend contaminate particles so they may be removed by the filter. Resistance to high temperature oxidation is probably the most important benefit that synthetics offer. It is especially important in turbos. Engine failures caused by oil oxidation, is the #1 lubrication related engine failure mode. Quote Link to comment Share on other sites More sharing options...
Mudge Posted November 7, 2002 Share Posted November 7, 2002 Viscosity modifiers are also going to result in faster break down of the oil, so dino loses out once again This is probably in some portion, part of the reason that race cars use a straight weight oil. Quote Link to comment Share on other sites More sharing options...
Guest De Schmaydee Posted November 9, 2002 Share Posted November 9, 2002 thanks for answering my question g.... ......s Quote Link to comment Share on other sites More sharing options...
johnc Posted November 9, 2002 Share Posted November 9, 2002 > part of the reason that race cars use a > straight weight oil. Let's see... 2001 SCCA CSCC ITS champ uses Mobil 1 15W-50 2000 ALMS GTS runner up uses Mobil 1 15W-50 2001 ALMS Paul Revere 250 winer uses Redline 15W-50 1999/2000/2001 Chili Bowl SuperSprint winner uses Mobil 1 15W-50 In racing, your biggest concern regarding oil is keeping the temperature down. Worrying about additive packages, etc. is a waste of time. Keep the oil as cool as you can. If you can keep the temps consistently under 220 then regular oil is fine. If your temps creep up and run at 240 consistently then a synthetic is a better choice. A spike now and then in temp doesn't instantly "kill" the oil. I've seen 260 on regular oil and 310 on synthetic and later chemical analysis showed no probblems. BTW... for a street car you biggest concern should be the detergent package. I have yet to see a street car consistently run its oil temps up around 220 (except maybe a poorly tuned Bug on a hot day). Quote Link to comment Share on other sites More sharing options...
Mudge Posted November 12, 2002 Share Posted November 12, 2002 Hmm, interesting. There is a local guy with a built up big block (700 something HP NA + big nitrous shot), and his builder recommended non-synthetic 15w-50, recommending non synthetic seemed the most odd... So I suppose possibly a straight weight oil is a thing of the past? Quote Link to comment Share on other sites More sharing options...
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