Conventional question

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I've long thought that synthetic was better than conventional when it comes to high temperature conditions (like in rings). But is that still as true as it was? Can a good conventional be better than a cheap synthetic in regards to handling heat?
 
Well, maybe!
I mean, it depends on the additive package of both oils. You know e.g., Pennzoil conventional(PYB) vs., oh lets say, some no name synthetic oil from a discount store.

Or, for the same price, I would take e.g., Super Tech(ST) Synthetic(or ProLine/AAP/AZ syn's etc.) vs. PYB conventional. Sometime, PYB is in fact more money than those said syn. But, they're all good!
 
I figure, it's splitting hairs, but why not split when there is nothing else better to do?

IIRC my 5S-FE is "known" for running hot in the rings. Hotter than anything today, or just hotter than normal back in its day? Dunno. I've figured cheap synthetic is better than conventional, but while that may have been true at one point, maybe it isn't anymore.

It's a few bucks either way, not breaking my wallet (so I've been using cheap synthetic) but question remains. I figure the engine really isn't up for 10k OCI's, so does it really need synthetic? OTOH it can & does get flogged for highway merging.
 
I have similar concerns. Will use Cheveron Supreme 10w-30 I have in stock this summer but have a concern of ring deposits. I guess after years of having a Saturn I never want coked rings again in any car.
 
Depends on the oil in question. Chevron Supreme is good oil for lots of engines including modified ones that get beat on. Speedol from the dollar store, not so much ...
 
Originally Posted By: BrocLuno
Depends on the oil in question. Chevron Supreme is good oil for lots of engines including modified ones that get beat on. Speedol from the dollar store, not so much ...


Thanks. I have trust issues regarding oil and am not very technically inclined. Part of me knows it is OK. You confirmed what I know, but still hard to let go of fear/doubt.
 
Originally Posted By: supton
I've long thought that synthetic was better than conventional when it comes to high temperature conditions (like in rings). But is that still as true as it was? Can a good conventional be better than a cheap synthetic in regards to handling heat?

In short the answer is no. Synthetic no matter how cheap it is has more uniform or same size molecules and therefore will dissipate heat at a better and faster rate than conventional oil can ever do.
 
My "hang up" over conv. vs synth. (and I love both) is that there CAN'T BE ANY PARAFFIN OR "NON OIL" JUNK IN THE SYNTHETIC OIL.

I'm sure you can burn or coke anything if the temp is high enough. I just guess synthetics give you a better shot at initial cleanliness.

I also guess the mechanics of it is that the oil stays liquid and keeps circulating.

I'd suppose the little oil holes in the piston skirts of those Toyota engines stay clear.
 
Originally Posted By: Kira
I'm sure you can burn or coke anything if the temp is high enough.

Indeed you can but due to uniform molecules and highly hydrotreated, synthetics just burn much cleaner than conventional oils.
 
You guys have been drinking the syn coolade too long. I want to know how much actual temp difference there is between the 2. Not just internet dribble. No matter what you use your motor will last longer than the rest of the car.
 
Sort of true. The ring pack can get hot, but the adjacent cylinder wall should only be maybe 100*F above the water jacket temp, even under load. So as long as there is coolant in the system, there is a practical limit to the upward temp possible.

High quality dino oils will live at 300*F. It's often the viscosity modifiers that burn off and cause coking. So it comes down to the add pack, not the base oils (in many cases) as to what is causing the coking issues.

"Most" synthetics are premium oils and have premium add paks. "Some" dinos are not. So the disparity between the accepted characteristics of dino vs syn. But there are no real hard fast rules. No one can show me a proffessional paper that proves that XYZ engine would have lived longer on say AmsOil than Chevron Supreme ... Or Mobil1 vs PYB ... There is no proof that synthetics actually lube better than premium dino oils.

It depends on the engine topology and the add pak in question. If you buy a name brand quality oil, it will serve you well. You buy el cheapo garbage, you pay the price. Syn vs Dino makes little difference.
 
Originally Posted By: BrocLuno
Sort of true. The ring pack can get hot, but the adjacent cylinder wall should only be maybe 100*F above the water jacket temp, even under load. So as long as there is coolant in the system, there is a practical limit to the upward temp possible.

High quality dino oils will live at 300*F. It's often the viscosity modifiers that burn off and cause coking. So it comes down to the add pack, not the base oils (in many cases) as to what is causing the coking issues.

"Most" synthetics are premium oils and have premium add paks. "Some" dinos are not. So the disparity between the accepted characteristics of dino vs syn. But there are no real hard fast rules. No one can show me a proffessional paper that proves that XYZ engine would have lived longer on say AmsOil than Chevron Supreme ... Or Mobil1 vs PYB ... There is no proof that synthetics actually lube better than premium dino oils.

It depends on the engine topology and the add pak in question. If you buy a name brand quality oil, it will serve you well. You buy el cheapo garbage, you pay the price. Syn vs Dino makes little difference.


+1
 
+2

I agree with Brucluno as well. Very well stated.

I will say though when I can get a group 3 oil made by Warren Distribution for $3.29 a quart.. I will be all right with that as well.
 
Originally Posted By: BrocLuno
Sort of true. The ring pack can get hot, but the adjacent cylinder wall should only be maybe 100*F above the water jacket temp, even under load. So as long as there is coolant in the system, there is a practical limit to the upward temp possible.

High quality dino oils will live at 300*F. It's often the viscosity modifiers that burn off and cause coking. So it comes down to the add pack, not the base oils (in many cases) as to what is causing the coking issues.

"Most" synthetics are premium oils and have premium add paks. "Some" dinos are not. So the disparity between the accepted characteristics of dino vs syn. But there are no real hard fast rules. No one can show me a proffessional paper that proves that XYZ engine would have lived longer on say AmsOil than Chevron Supreme ... Or Mobil1 vs PYB ... There is no proof that synthetics actually lube better than premium dino oils.

It depends on the engine topology and the add pak in question. If you buy a name brand quality oil, it will serve you well. You buy el cheapo garbage, you pay the price. Syn vs Dino makes little difference.


And now for the 0w20 discussion …
 
Interesting; thanks. Just wondering about future options. The car gets about 2k/month thus oil changes are kinda often (I keep to a 5k OCI). Sounds like I just need "good" oil and that this engine really isn't different than anything else out there--back in the day, oils were worse, long OCI's were not its friend, and we're past that now (better oils and keeping to short OCI's).
 
Best deals for name brands these days are synthetics in five quart containers.
Example: Walmart has Castrol Magnatec Synthetic for like 17.88 (five quart jug)
Pennzoil Platinum Synthetic can be yours for $15.... after $10 rebate.

In conventionals, I just bought two cases of Formula Shell for $1.75 qt (after $5.50 store rebate from Menards)
 
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Right now I'm using up some Mobil Super Synth that I got for $20/6qt. I prefer the single quart containers, this car takes 4 quarts. Once I start getting towards the end of this stash I'll start thinking of what to use next (or save it for the other vehicles, those I don't plan to use conventional, ever).

Usually whenever someone says "there oughta be a law" it's a good indication that whatever follows shouldn't be a law. But IMO all cars should take nice round numbers of quarts! At least rounding up a quart seems to harm nothing. Now if they could just standardize on increments of 5 quart capacities (5 quarts for cars, 10 for trucks), then I'd be all over buying 5 quart containers.
 
^^^^^

That's a good point. And I agree. Be nice if it was standardized. I also prefer qt size containers. I just got 10 Federated Auto full synthetic oil qt containers for $3.29 a quart.
 
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