Worse mileage with synthetic (and Bosch Platinum +4's)?

[Daox]

I agree about synthetic oil. I normally run 10k miles on my synthetic and usually do an oil analysis when it gets changed. There are never abnormally high amounts of particulates in the oil.

I'm not sure what you're saying about fuel cut on deceleration. Most modern cars do turn off fuel injection entirely during in gear deceleration with a manual transmission. I have a gauge that measures the PWM signal to the injectors, so I can say this for fact. I know not all cars do it, but I haven't heard of any 2000+ cars that don't.

[AveoRob]

Synthetic does improve fuel economy

Can you point me to some scientific data to prove this?

[petrified.rabbit]

He can point you to all the information that proves it is true, just as well as someone can point you to all the information that says it is not true.

[Unidentifiable]

1. Synthetic does not improve fuel economy for the same weight of oil. It does afford a longer OCI, which has been proven over and over again. If you change your oil from 5w30 Dino to 5w30 Syn, you're just going to get better oil (opinion, subject to differences) and a longer OCI (proven on many accounts).

2. Fuel cut does exist. It's programmed into just about as many OBD-II vehicles as I can recall, although I'm surely not thinking of a few that don't have it. It does not exist on carburetor equipped vehicles, except a select couple which had technology to prevent fuel flow on deceleration, under heavy vacuum.

3. Of course, anyone can seek out and find information which "tells the truth" about what they're trying to say, and of course, said information will always directly support that person's POV. It's the reader's job (lurkers, too) to distinguish what of that information is suited to them, and which they choose to believe.

Remember, you can only tell the truth - you can't make anyone else believe it.

[petrified.rabbit]

Thank you.

But another thing to watch out for synthetic oci, if you read the fine print many of them say you need to follow your factory recommended oci. Therefore if you have a warranty and are only doing oil changes every 10k because you made the switch, the factory wont replace your engine.. and the oil company won't back you up.

Any time i have done engine under warranty work it has been required of the owner to provide proof of all oil changes to the factory for the exchange. If they could not provide proof within 500-1000 tolerance (typically) for the oil changes (we only required the last 3) with the recommended intervals then they would need to pay for the work. Warranty probably wouldn't cover it.

[NorthernAveo]

Synthetic does improve fuel economy

Can you point me to some scientific data to prove this?

http://www.bobistheoilguy.com/forums/ubbthreads.php

Hope you have a couple months.

[NorthernAveo]

Thank you.

But another thing to watch out for synthetic oci, if you read the fine print many of them say you need to follow your factory recommended oci. Therefore if you have a warranty and are only doing oil changes every 10k because you made the switch, the factory wont replace your engine.. and the oil company won't back you up.

Any time I have done engine under warranty work it has been required of the owner to provide proof of all oil changes to the factory for the exchange. If they could not provide proof within 500-1000 tolerance (typically) for the oil changes (we only required the last 3) with the recommended intervals then they would need to pay for the work. Warranty probably wouldn't cover it.

You can have an oil analysis done and prove that the oil was perfectly fine when a failure happened. This takes a week to Blackstone Labs in the US and Wearcheck in Canada and they provide back a detailed report stating all the wear metals and the TBN (Total Base Number) of the oil.

I am not going to go into the "prove it" arguement to tell people that synthetic oil helps in increasing fuel economy and engine cleanliness. Anyone that knows engine oils knows what I am talking about.

It is mostly the cheap car owners that will find any excuse not to use it seeing it costs more so they will put it down or make up why it shouldn't be used. These people usually use Fram oil filters as well.

[AveoRob]

Synthetic does improve fuel economy

Can you point me to some scientific data to prove this?

http://www.bobistheoilguy.com/forums/ubbthreads.php

Hope you have a couple months.

Hmmmm....I thought I said scientific. I don't think a forum website qualifies. Please explain the physics behind your claim that synthetic oil improves fuel economy. I understand about longevity and lower operating temperatures and all of the other benefits of synthetic oil, but please show me the empirical data showing improved fuel economy.

I know it's human nature to think you are getting better mileage since you paid all of that extra money, bit if there was a noticable, measurable cost effective improvement in mileage, don't you think they would advertise it?

[NorthernAveo]

Hmmmm....I thought I said scientific. I don't think a forum website qualifies. Please explain the physics behind your claim that synthetic oil improves fuel economy. I understand about longevity and lower operating temperatures and all of the other benefits of synthetic oil, but please show me the empirical data showing improved fuel economy.

I know it's human nature to think you are getting better mileage since you paid all of that extra money, bit if there was a noticable, measurable cost effective improvement in mileage, don't you think they would advertise it?

Read the forum, all they do is talk about oil. I am not going to do the work for you. That site has the most infomation on oil on the internet. It is full of scientific discussion from industry reps and oil testing scientists from around the US.

Actually, they do advertise it. And seeing the oil doesn't thicken as much and its kinematic viscosity allows for quicker warmup and better colder temperature economy and lower viscosity, it does make a difference.

[NorthernAveo]

It is mostly the cheap car owners that will find any excuse not to use it seeing it costs more so they will put it down or make up why it shouldn't be used. These people usually use Fram oil filters as well.

When I traded in my '86 yoda truck it had 255K worth of miles on Fram filters and dino oil. I got 1K for it. Do you think if I used syn oil and mobil 1 filters I would have got more as a return on investment?

If you knew anything about the internal construction of a Fram oil filter, you wouldn't be making that claim. It has 50% less filter media, cardboard internal construction and most over time collapse internally and have a nitrile anti-drainback valve that hardens quickly and allows the oil in the top end of the motor to drain back into the oil pan causing a dry startup knock and increased startup wear.