steviej

iTrader: (1)

I t hink you will find that most of "these synthetic oil companies" offer conventional oils, too.
Mobil, Penzoil, Valvoline, Castrol, Amsoil, Quaker State, Kendall, NAPA, etc.

I use synthetic mainly for one reason: I am in New England and the winters can be extremely cold. I am talking <10°F for weeks on end. Synthetic is more liquid than conventional at these lower temps so initial startups at extreme cold temps are not as harsh as they would be with conventional oils. If I were in a warmer climate, conventional would do the job just fine.

steviej

Spyder187

That's the insurance I've got. I cover liability but not much of anything else. A little scary in the event I should hit a deer or something but for $300 more, I'm thinking the chance of it happening doesn't outweigh the cost even though I wouldn't be able to replace my car if that happened.

Anyways as to the engine oil debate, doesn't Mobil have that ad with the Mercedes in it? The only thing wrong with the ad is that the car was driven for long distances at a time thus engine wear as the engine oil was always circulating through the engine. In real life, as someone posted, most engine wear occurs when the engine isn't properly lubricated as at the time when we just start our cars after not driving it for a extended period of time, ie. in the morning.

I'm just using normal Quakerstate oil or something like that and the coldest it reachest around here is about -15 to -10C, should I start thinking about switch to synthetic for the winter?

I find though that these Toyota engines are solid and as long as oil changes are kept to schedule, about 5000km per change for me, then engine wear shouldn't be much of a worry.

ellwood

There's no debate about the fact that every synthetic oil maker has failed to provide the public with scientific proof that synthetics significantly reduce engine wear / extend engine life. That's likely because synthetics don't really have those capabilities.

There's no debate about the fact that virtually no Toyota / Lexus owner has ever had to junk their car because the engine wore out due to the use of conventional instead of synthetic oil. This includes owners living in cold and hot climates.

Toyota / Lexus owners do, however, commonly junk their cars or buy rebuilt engines because they ruined their factory original engines by letting them run low on oil or coolant, letting them run too long on dirty / worn out oil, coolant or filters, using other than the factory recommended viscosity of oil, letting them run hot, letting them misfire, never checking and adjusting the valve clearances, overevving the engine or severely lugging the engine and that sort of thing.

Common Sense Conclusion: The last thing a Toyota / Lexus owner should be concerned about if they wish to ever become a member of the Toyota 400,000 mile club is worry about their choice of synthetic vs. conventional oil.

HarrierAWD

True in both accounts, but....

However, synthetic oil sells at much better margin. So even companies like Mobil & Pennzoil would heavily promote synthetic oil.

I use dino 5W-30 and started at minus 10F on occasions without any problem. Here's a suggestion: leave a bottle of dino 5W-30 out overnight and see how it flows next morning.

I like this oil discussion/debate this time around. People are keeping it civil.

HarrierAWD

Some people use synthetic oil because they think it's better than dino for their beloved rides, at least it supposely won't hurt. Believe it or not, there are good reasons NOT to use synthetic other than just a waste of money. Here are a few that I know:

Oil burning - Synthetic oil is more likely to seep past the piston rings and get into the combustion chambers. It gets burned off. Some reported burning one quart between oil changes after switching to synthetic. Its deposit may coat the oxygen sensor ($$$ to replace,) the back of exhaust port valves (gives you compression problem overtime,) clog up the PCV valve, and catalyst converter. It won't make the car die or fail emission inspection overnight, but its cumulative effect will later on.

Oil leak - Synthetic oil is more like to seep past worn engine gasket and cause oil leak. As the car ages, you may see oil on the engine or in the coolant. The gasket is a $20 part, but the labor involved will cost hundreds, even more with coolant flush. Also it's hard to keep engine bay clean when you have an oil leak. Some resorts to hosing down the engine bay with water and cause electrical malfunction later on (no matter how careful you do it.)

Cold start (in typical climate, not Arctic Circle) - Synthetic oil flows down to the oil pan faster than dino oil. Leaving some engine parts starved of oil during the first few seconds of startup.

Cold start (in Arctic Circle) - synthetic would be nice, but when the battery is frozen at -40F or below, can you start the car?

Heat protection - Yes, synthetic oil has flash point roughly 40F higher than dino oil. Typical engine operating temperature is about 220F to 280F. Dino oil has flash point at about 400F. Synthetic at about 440F. (varies by brand) So they both can handle typical engine temperature very well. When something goes wrong with the engine - say loss of coolant - temperature can shot up to over 1,000F quickly. Having 40F higher flash point will get you maybe 100 yards farther down the road before the engine seizes. Big deal.

Extended change interval - Some synthetic users extend their change interval to get their money's worth. Bad idea. The engine will put the same amount of contaminants into the oil, no matter dino or synthetic. Some contaminants cannot be filtered out and can only be eliminated by oil change. By keeping longer intervals, these people are actually harming their engines and don't know it. Oil test won't help since sludge sits on engine parts, not in the oil so it won't show up in the lab results. Using dino oil will keep most people change oil regularly. Also their tech can help inspect the vehicle during oil change.

Still think using synthetic is better? Feel free to comment, but keep it civil please.

beachdrive

I agree this is one of the best discourses in a while. I would like to hear from as many people as have thoughts on this one. I have seen a whole new range of opinions and realize that my previous position in favor of syns is not as rock solid as it was.

steviej

iTrader: (1)

actually, I several of us have done that. The conventional pours much slower than the synthetic as expected.
I will go you one better, don't use your household frost free freezer. these cycle the temp on and off to eliminate frost build up.

I did the little experiment in a constant freezer at -20°C (-4°F) for 24 hours. The dino oil was moving much much slower than the synthetic.

steviej

ellwood

I've done a bunch of zero degree freezer tests too. I found both the synthetic and dino 5W-30 oils flow slowly at zero degrees F, although the synthetic flowed slightly faster. At -5 below zero,
however, the synthetic was flowing as slowly as the dino oil did at 5 degrees about zero. Conclusion: the cold weather advantage of synthetic is slight, not major.

I also feel it is more important to ask the question: "Even if synthetics slightly reduce cold weather start up wear, is this start up wear significant to begin with? My personal experience and research has led me to believe Toyota engine parts will not suffer hardly an wear that can be measured, seen or felt unless subjected to trauma of some sort like running low on oil or coolant. running too hot, running with the engine misfiring and that sort of thing.

HarrierAWD

I guess test results can vary from person to person. We all know that synthetic flows better at below freezing temperature, but the advantage may be slight.

Here in Colorado, the typical winter morning temperature is about 10F. 5W-30 dino oil can handle that easily. My garage is usually at 45F in the morning. Piece of cake for dino. Late afternoon temperature is usually 40-50F at work.

The lowest startup temperature I ever had was -11F in Vail. My RX300 was parked outside overnight and it started right up. The engine didn't sound any different. Of course, I let it warm up about 3 minutes before I drove off. Had to clear snow and ice anyway.

So what's the typical temperature in your neck of woods?

Lexusfreak

Did the same experiment in my deep freezer a year or so ago. The poor dino oil! It wasen't even close.

steviej

iTrader: (1)

Mid March to November is is similar to yours. December to Mid March anything goes.
The last couple of years we have had 3-4 weeks at a time that the highest temp was a single digit.

The picture I have include is now part of a typical commute in the winter. That is ocean saltwater that is freezing, not lake fresh water. Trust me, winters in Boston are very very cold.

I don't disagree with you on your beliefs, but again the bottom line to any oil thread: good for you is what makes you feel most comfortable. Right now I feel more comfortable with synthetic and a regular change interval of 5000 miles.

steviej

OceanView

One thing that I noticed is that the oil color changes differently on my cars.

I use Mobil 1 on both of my cars. I change every 5000 miles on my Mercedes and 7500 on my Lexus. Reason is that the oil in the Lexus is always cleaner than in my Mercedes. Note sure why, Both cars are driven the same, both about 70% highway and both 6 cylinders. Both have over 150,000 miles. Mercedes has recommended Mobil 1 and so I used it from the begining and the Lexus used dino til about 70,000 miles then switched to Synthetic. I could switch the Lexus back to dino and feel that it would be ok. But I don't think I could do that for the Merc.

Anyone else notice different rate of oil color changing?

parula

My synthetic oil stays a lighter amber color longer - I am sticking with synthetic for this baby, regular 5k intervals at least during warranty.

1993ES300x

sorry to bring this up guys.. but i always scratch my head when shopping for oil.. what the hell is this syntec blend that castrol carrys?? is that like left over from all the good syntec oil. that's on the button ??

and what the hell is Moble 1 doing .. they have syntec oil and they have advance syntec or the super syntec.. what the hell is up with that??..

last question.. switching from castrol syntec to moble 1 is no problem , right?? i don't need to flush the engine before or anything like that, right???

steviej

iTrader: (1)

1. synthetic blend is a combination of conventional oil and synthetic oil (% of each type vary between manufacturers).

2. Mobil 1 is changing their marketing scheme.
I believe the oils are now labeled as mileage
5000 is conventional.
7500 is a blend.
15000 is full synthetic.

3. switching from one oil to the other is not a problem and generally no flush is necessary.

steviej