Group III 5-50 vs. Group IV 10-60???

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Guys, which do you think has more VII's in it....a Group III (eg. Castrol Syntec) 5w-50 or their Group IV (supposed PAO) TWS 10W-60?? Why?? Which would leave more deposits? Does it matter that one is a Group III and the other a Group IV?
 
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I doubt their 5W-50 is all GIII ....... with that spread, it must have some GIV or GV in there ..... it would also seem to me the oil that has more VIs .......
 
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I think I would pass on both of them. If they achieved this spread with the combination of esters base stocks then I would be all for it. If it is all group III with VII'S then I would leave it alone.
 

Patman

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I think a 5w40 would be a much better choice compared to those other two. I can't think of any engines out there which would benefit from using 5w50 or 10w60. I'd even be willing to bet the BMW M3 engines would show excellent results using Redline 5w40 compared to that 10w60 oil they call for now.
 
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Patman...
quote:
I'd even be willing to bet the BMW M3 engines would show excellent results using Redline 5w40 compared to that 10w60 oil they call for now.
At a cost rumoured to be around 12 k per M3 engine...that is a really big bet...!!! Any M3 owners willing to take Patman up on his "bet"? [Eek!]
 
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See M3 engine not working anymore... http://members.roadfly.org/jason/m3engines.htm Look on left side menu bar...scroll WAYYYYYY! down to engine failure 130 !!! (yes...130!!!) See nasty engine stuff... [Big Grin] And Patman...some pic's here with BMW M3's with big pools of some kind'a GREEN stuff under them? I think it's, oh my, GC...!!!??? (Just kiddin)!!
 

Patman

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The M3 engine failures were later traced to bad bearings, not the oil, although 5w30 is probably still too thin for them. But Redline 5w40 is a middle 40wt oil, with an excellent HTHS and this oil does not shear back easily either. I'd be willing to bet the 10w60 oil does. So in the long run, you'd be better off with Redline in the M3.
 
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The PAO based, 10w-60 will have much less VI modifier than a 5w-50, group III based oil. However, I suspect the Castrol 5w-50 does contain at least 20% PAO - it would be difficult to achieve the required "viscometrics" otherwise. In the case of the 10w-60, you could start with a 10 Cst or 12 Cst, PAO and add some VI modifier or "supersyn" PAO (they do sell the SS to other companies). All the Group III basestocks I've seen are 4 Cst fluids @ 100C. So you have to thicken the heck out of them to even make a 15 Cst, SAE 5w-40, much less an 18 Cst, 5w-50.
 
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I also think Castrol TWS 10W-60 will be more resistant to shearing and leave fewer deposits. I don't think the difference will great. The viscosity index of 198 for the TWS will likely still require a significant amount of viscosity index improvers. The TBN is only listed as 8.1 which is not very high. If I had to choose between TWS 10W-60 and Syntec 5W-50 I would choose the Syntec for anything other than all out racing. The Syntec 5W-50 may be made-up of mostly group III however the viscosity index is "only" 175 as apposed to 198 for the TWS. Also the TBN for Syntec 5W-50 is about 10.5. Chevron and ConocoPhilips now offer group III base oils in a 7 cSt viscosity @ 100 C. I don't know how much of a difference that will make in formulating a high viscosity group III base oil. Dr. T, have you ever considered trying Auto-Rx in your BMW? Some of the results people have been having seem to be remarkable. My wifes BMW 318i has a small amount of sludge under the valve cover where there is very little oil flow. Neutra 131 got rid of about 95% of the sludge and varnish that this car had but I am trying Auto-Rx to see if I can remove the remaining 5% or so of the leftover crud. Many people have reported lower oil consumption after using Auto-Rx for a short time. 10W-60 just seems a little thick for the winter in Canada. [Canada] [ December 03, 2003, 09:22 AM: Message edited by: Sin City ]
 
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quote:
Originally posted by Patman: The M3 engine failures were later traced to bad bearings, not the oil, although 5w30 is probably still too thin for them. But Redline 5w40 is a middle 40wt oil, with an excellent HTHS and this oil does not shear back easily either. I'd be willing to bet the 10w60 oil does. So in the long run, you'd be better off with Redline in the M3.
I still think the point is that I'd use what BMW recommends under warranty. I've got two BMWs under warranty and I like GC because it meets all requisite specs. I've got a boatload of Schaeffer's that I won't use on my in-warrany BMWs because its not "full syn" or BMW LongLife approved. However, I think the Schaeffer's would do as well as the "factory" BMW syn. I really like BMWs, but repairs can kill you. BTW, my old 86 BMW was sold at 197k and had little if any consumption with xW30 it whole life. Jack
 
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quote:
Originally posted by geeeman: See M3 engine not working anymore... http://members.roadfly.org/jason/m3engines.htm Look on left side menu bar...scroll WAYYYYYY! down to engine failure 130 !!! (yes...130!!!) See nasty engine stuff... [Big Grin] And Patman...some pic's here with BMW M3's with big pools of some kind'a GREEN stuff under them? I think it's, oh my, GC...!!!??? (Just kiddin)!!
"Due to contamination of the engine lubrication system during engine assembly in combination with unfavorable tolerances in the oil pump, the connecting rod bearings can be damaged which my lead to their overheat and possible engine failure..." So much for gods heaviest oil this side of wheel bearing grease being the solution for all problems...
 
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quote:
Originally posted by palmerwmd: The 10w-60 sgould have fewer VII's especially if its a PAO. Fred.. [Smile]
It is an interesting brew of group III , pao and diester so I'm led to believe . I wonder what the largest spread in history is ?
 
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Hi All, If you read carefully through the roadfly M3 thread you will note that there did not appear to any greater occurance of failure in the engines running 5w-30, possibly less. As a coincidence the oil grade was changed back to 10/60 early in the period when most failures started to appear. The problem was a material/ manufacturing fault, not oil.
 
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Yes...It seems the change in oil spec to the 10W60 was simply a short term "we don't know exactly why they're blowing up, hope this helps" kind of deal... [Confused]
 
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From what I read this isn't the case. The cars came with 10w-60 from the factory, but the US dealers changed it to 10w30 as it was thought that the cars wouldn't be driven as hard as Europe due to their Autobarns. BMW found out that this wasn't the case and told US dealers to put what was factory fill back in. Then again, what I read may be wrong!
 
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