Synthetic or Dino

[Yup]

Originally Posted By: Garak
The only way a synthetic is really going to help in the winter is, assuming the weather justifies it and you're choosing a grade that isn't really available in conventional. For example, a 0w30 will have better cold cranking numbers than any 5w30. A synthetic 5w30, however, does not guarantee better cold weather performance than a 5w30 conventional.


I'd bet my life synthetic 5w30 flows faster and better than any conventional 5w30 you can find. Ever put them in a jar during the winter? The whole purpose of synthetic is a wider range of temperature usage along with, typically, more robust additive packages.

 

[Shannow]

Originally Posted By: Yup
I'd bet my life synthetic 5w30 flows faster and better than any conventional 5w30 you can find. Ever put them in a jar during the winter? The whole purpose of synthetic is a wider range of temperature usage along with, typically, more robust additive packages.


Doing a fair bit of betting lately...

What sort of flow are you talking about ?

Like wriggling a jar around at -30C ?

In order to be a 5W, they are going to be extremely similar.

 

[Mattz]

ok guy thanks .. I am going to try to look down my oil fill hole with a flash light see what I can see.. maybe see if I can get my hands on one of those fiberoptic cams lol

 

[Garak]

Originally Posted By: 901Memphis
Some of the 5w30 synthetics can actually be thinner than a 0w30 around 0C until it starts to go negative so much.

Oh yes, certainly, but I'm speaking of the cold crank numbers where cold crank actually matters in this case. At 0 C, it isn't going to matter a hill of beans even using a 10w30.

Originally Posted By: Yup
I'd bet my life synthetic 5w30 flows faster and better than any conventional 5w30 you can find.

No, we've been through that flow argument here countless times. Rate of flow doesn't change with a positive displacement oil pump. Secondly, ultra-cold performance depends upon CCS and MRV, not simply upon base stock. Further, pour point is not the issue here. I can find 15w40 HDEOs with a much lower pour point than various 5w30 synthetics.

 

[Garak]

Originally Posted By: Yup
I'd bet my life synthetic 5w30 flows faster and better than any conventional 5w30 you can find.

In fact, I already found one counterexample, off the top of my head, and checked the data sheets to confirm. Petro-Canada's conventional 5w30's MRV is 15200 cP at -35 C. Petro-Canada's synthetic 5w30's MRV is 15700 cP at -35 C.

 

[Oregoonian]

Originally Posted By: tig1
A quality synthetic is always a better choice in a good sound engine.

+1.....especially for a short-tripper as well as in cold weather.

I would suggest Quaker State Ultimate Durability (a little more reasonable oil), and if just doing 5000km, ann OCI of 2 years.

 

[Mattz]

I was either going to use Quaker state ultimate durability or Pennzoil platinum. Today I opened the oil fill cap took a flash light can't really see anything but black plastic..that being sayed I really don't want to start ripping my car apart to see if there is any sludge the car is mint engine is spotless so I might switch over this week maybe run the first run for 2500 km then drain and refill and run it 5000 km. Would there be a change if there was any sludge it could clog up the screen or will the oil brake it down?

 

[Gasbuggy]

OP there a user on this forum with a R/T Charger that has something like 250,000 miles on it and has consistently great oil analysis results with what oil I forget. I would check the used oil analysis section, it should be in the first few pages. Run whatever he runs.

 

[Yup]

Originally Posted By: Garak
Originally Posted By: Yup
I'd bet my life synthetic 5w30 flows faster and better than any conventional 5w30 you can find.

In fact, I already found one counterexample, off the top of my head, and checked the data sheets to confirm. Petro-Canada's conventional 5w30's MRV is 15200 cP at -35 C. Petro-Canada's synthetic 5w30's MRV is 15700 cP at -35 C.


That's over my head. I've done the "oil in a mason jar" backyard test numerous times with different conventional and Syn oils of the same weight. Syn always poured better. Explain to an idiot, in simple terms, how it performs the same in an engine but different in my mason jars. I'm not arguing your data, I just honestly don't get it. According to your data, ignorance is bliss for me! Lol

 

[Garak]

MRV is a measure of actual pumpability, which is what you're after in the cold. The conventional PC 5w30 has better pumpability in the cold than the synthetic. The synthetic would probably pour better out of the freezer, but the engine pumps oil. Synthetics are usually better, but the main advantage to synthetics is you can get a 0w-XX as a synthetic or a blend. Grades are available in synthetic (or blends) that otherwise aren't available. The following video shows pouring demonstrations and pumping demonstrations. In this video, considering that they're using a 0w-30, the oil has a better pour point and better cold cranking properties, because the latter is the goal of the viscosity in question.



Do not that Royal Purple's 15w40 has a pour point around -46 C. It's a synthetic. I'd chose a 5w30 conventional over it any day of the week when it's -35 outside, since 15w40 will not pump properly at that temperature (regardless of pour point) where the 5w30 will, conventional, blend, or fully synthetic.

 

[BigD1]

From what I have read, Castrol is readily available in Canada, so I would either use Castrol GTX/Pennzoil conventional, and change it every six months, or use the Castrol 5w-20 Magnatec which is a full synthetic, and change it once a year.

 

[Mattz]

ok thanks for the info. I pulled the engine cover noticed that the pvc canister thng was caked in oil? going to replace the pvc valve ill try to snap a picture.. would conventional oil hold up the hard driving which I intend to put through this summer possibly track use?

 

[Yup]

Originally Posted By: Yup
Originally Posted By: Garak
Originally Posted By: Yup
I'd bet my life synthetic 5w30 flows faster and better than any conventional 5w30 you can find.

In fact, I already found one counterexample, off the top of my head, and checked the data sheets to confirm. Petro-Canada's conventional 5w30's MRV is 15200 cP at -35 C. Petro-Canada's synthetic 5w30's MRV is 15700 cP at -35 C.


That's over my head. I've done the "oil in a mason jar" backyard test numerous times with different conventional and Syn oils of the same weight. Syn always poured better. Explain to an idiot, in simple terms, how it performs the same in an engine but different in my mason jars. I'm not arguing your data, I just honestly don't get it. According to your data, ignorance is bliss for me! Lol



But wouldn't the much lower CCV of the Syn 5w30 also play into why it's better in the winter? Petro CA's website says Syn is better in cold temps. Can't imagine they don't mean it.

 

[Garak]

CCS is only part of the issue, and MRV is actually the more useful number. That's the measure of its pumpability at that temperature.

Generally, as was already mentioned, a synthetic 5w30 will outperform a conventional 5w30 in the cold. However, as I noted, there is no guarantee. My primary concern would be that the oil meet the 5w-XX or 0w-XX requirements, or whatever requirements you're looking for. After that, it is really splitting hairs. If one isn't satisfied with one 5w-XX and wishes to hunt between different 5w-XX examples, they might be better served going with a 0w-XX in the first place.

Petro-Canada's point that synthetic is better in cold temperatures is a very vague, generalized statement. Every oil company and parts store repeats that like gospel, without actually explaining what is meant by the statement and what limitations there actually are. The biggest advantage to synthetics in extremely cold conditions is that you can get grades that aren't otherwise available. You're not going to find a 0w30 conventional, whereas you will easily find a 5w30 conventional, and the 0w30 will have better CCS and MRV numbers than the 5w30, by the very definitions of the grades.

 

[Kuato]

Originally Posted By: Mattz
Hello guys and gals. I just recently Purchased a 2008 Dodge Charger R/T with 95000 km on her. I was thinking of switching to synthetic but I wonder if ill have any ill effect on the motor ? Should I flush the motor or will the synthetic clean everything up the first change, I am hopping it is ok to run for a year I am lucky to reach 5000 km a year. and I have to use 5w20 for MDS to be in effect or sould I just stick with the good conventional oil and change it twice a year worried about sludge issues with all the short trips and moisture not being burnt off.. hope to hear every ones feed back thanks in advance.


I've switched several vehicles that I bought to synthetic, some with as many as 170k km. Some developed a slight leak, which went away after less than 5000km. When I say slight I mean some oil dampness around the seal and maybe a drop on the ground. But again, that stopped within the first OCI. So if your vehicle is in decent shape then it should be fine to switch.