When to switch to Synthetic oil?

Daniel,
Could you post the reference? I tried but couldn't find the reference on the Toyota site.

 

All I can say is that my Toyota Dealership gave me a free 1K Oil change with the car. They asked if I wanted to go to Mobil 1 at that time. I opted to wait til at least the normal 5K.

Howver, they were VERY explicit and repetitive in explaining that Toyota required that if you changed to Synthetic, you should not ever change back.

 

I don't think anyone is saying the car "needs" synthetic. I for one plan to switch to synthetic at my first 5000 mile oil change because I like the idea of using less dino oil.

 

From www.toyota.com select the FAQ page, and then "Synthetci Oil". Not sure I can make this work, but it should be here.

Here's the text, from the above-cited page:

All Toyota vehicles come from the factory with natural petroleum-based engine oil. Toyota is currently recommending API1 grade SJ or SL, or ILSAC2 multigrade petroleum-based engine oil3 for our current model year vehicles. In moderate climates, this oil should have a Society of Automotive Engineers (SAE) viscosity rating of 5W-30. In our high mileage tests with preventative maintenance performed at the recommended intervals, the recommended natural petroleum-based oil has provided excellent service.

If you decide to use synthetic oil for the engine, it is best not to switch until the first scheduled oil change. Synthetic oil should meet or exceed the specifications provided in your Owner's Manual. Even if synthetic oil is used, we do not recommend a longer oil change interval. Also, once synthetic oil is used, you should keep using it and not switch back and forth with natural petroleum-based oil.

The Toyota New Vehicle Limited Warranty does not cover any damage to the engine resulting from the use of engine oil that is defective, or that does not meet the specifications provided in your Owner's Manual, regardless of whether the oil is natural or synthetic. You can protect yourself against this possibility by having your maintenance performed by a factory-authorized Toyota dealership.

 

does anyone actually think that a synthetic oil company is going to say "no you shouldnt use our oil" at ANY TIME??

its obvious to me that Mobil 1 will say its ok to use synthetic oil right away. they are in the business of selling oil, NOT in giving advice on how to maintain your vehicle.

 

I just wanted to post this as a summary.

Part of the Mobil 1 FAQ

What is synthetic oil?

All motor oils are made up of base oils and additives. In general, fully synthetic motor oils contain non-conventional, high-performance fluids and a system of additives to help prevent wear, keep an engine clean, flow easily, maintain viscosity, prevent rust and reduce friction. The result is a lubricant that remains liquid and slippery under the widest possible range of temperatures and engine conditions.

What makes synthetic oil superior to conventional oil?

Historically, conventional oils lack the performance of synthetic oils in the areas of low-temperature performance and high-temperature oxidation stability. Conventional motor oil is made up of an inconsistent mixture of long and short chains of carbon and hydrogen atoms. In the extreme heat of an engine, short-chain molecules can evaporate, and unstable molecules can oxidize and break down. Conventional oils also contain much greater amounts of impurities, such as sulfur, reactive and unstable hydrocarbons, and other undesirable contaminants that cannot be completely removed by conventional refining of crude oil.

Mobil 1® with SuperSyn™ uses high-performance fluids, including polyalphaolefins (PAOs), along with a proprietary system of additives. Each Mobil 1 with SuperSyn™ viscosity grade uses a unique combination of synthetic fluids and selected additives in order to tailor the viscosity grade to its specific application.



"Myths about Synthetics"

You should break in your engine with conventional oil, then switch to Mobil 1.

You can start using Mobil 1 with SuperSynâ„¢ in new vehicles at any time, even in brand-new vehicles. In fact, Mobil 1 with SuperSynâ„¢ is original equipment (it is installed at the factory) in:

Chevrolet Corvette

All Porsche vehicles

Mercedes-Benz AMG vehicles

Dodge Viper

Ford Mustang Cobra R

All Aston Martin cars

One of the myths that persists about Mobil 1 is that new engines require a break-in period with conventional oil. Current engine manufacturing technology does not require this break-in period. As indicated by the decisions of the engineers who design these high-performance cars, Mobil 1 with SuperSynâ„¢ can be used in an engine from the day you drive the car off the showroom floor.

Using Mobil 1 will void my new-car warranty.

With the exception of the Mazda rotary engine (Mazda does not recommend any synthetic motor oils), Mobil 1 with SuperSynâ„¢ will not void new-car warranties. Mobil 1 with SuperSynâ„¢ exceeds the API and ILSAC motor oil service requirements of all new-car manufacturers, both import and domestic. If in doubt, always check your vehicle owner's manual or contact your vehicle's manufacturer.

You don't have to change the oil as often when using Mobil 1.

While Mobil 1 has given excellent results in extended oil drain tests, ExxonMobil prefers to remain conservative with oil drain recommendations. ExxonMobil engineers recommend that you can go all the way to the maximum mileage or time frame shown in your owner's manual for oil changes when using Mobil 1 with SuperSynâ„¢. This allows the reserve protection capabilities of Mobil 1 with SuperSynâ„¢ to cover unusual or unexpected driving conditions.

Oil change intervals can be as short as 3,000 miles or as long as 15,000 miles on some new cars. Mobil 1 with SuperSynâ„¢'s high-performance reserves can give you the confidence to go the full mileage or time frame recommended by the vehicle manufacturer. Mobil 1 with SuperSynâ„¢ is especially suitable for the latest vehicles with extended drain intervals or vehicles with oil monitoring systems that vary oil drain intervals.

I need to flush my engine before switching to Mobil 1.

No special preparation is necessary when switching from conventional motor oil to Mobil 1 with SuperSynâ„¢.

Mobil 1 requires a special oil filter.

While ExxonMobil recommends that you use a high-quality filter, you can use the same type of oil filter that you would normally use with conventional oil. ExxonMobil does offer a very high-quality oil filter that is a perfect companion to Mobil 1 with SuperSynâ„¢. The Mobil 1 High Efficiency Oil Filter contains synthetic fibers instead of the typical cellulose filter media. With a 95-percent efficiency rating (under SAE J806 tests for capacity and contamination removal), the Mobil 1 filter is much more efficient than a typical oil filter, removing more particles per pass through the filter. In addition, the synthetic fibers in the Mobil 1 filter have less resistance to oil flow, reducing the potential for the filter to restrict the flow of oil to your engine.

Mobil 1 will leak out of the seals of older cars.

Mobil 1 does not cause leaks. In fact, new Mobil 1 with SuperSynâ„¢ was tested in dozens of industry standard and OEM tests to prove its seal performance. It is fully compatible with the elastomeric materials from which all automotive seals and gaskets are made.

ExxonMobil engineers are wary of conventional oils that tout their use of additional seal-swelling agents. With extended use, these agents can over-soften engine seals, resulting in leaks. More to the point, an oil additive will not rejuvenate worn or damaged seals. The damaged seal may have been caused by a worn rotating metal component in the engine.

If an older engine is in good condition and does not have oil leaks, Mobil 1 with SuperSynâ„¢ provides the same advantages as when used in a new engine. ExxonMobil recommends taking measures to repair the leaks, then using Mobil 1 with SuperSynâ„¢. ExxonMobil also always recommends following the automobile manufacturer's manual for the proper oil to use.

 

Oil filters

I intend to go to Mobil 1 on my first oil change around 5000 miles. I run Mobil 1 and K&N filters in my '91 Landcruiser w/254k miles. Has anyone checked into "premium" filters for the Prius?

 

"One of the myths that persists about Mobil 1 is that new engines require a break-in period with conventional oil. Current engine manufacturing technology does not require this break-in period. As indicated by the decisions of the engineers who design these high-performance cars, Mobil 1 with SuperSynâ„¢ can be used in an engine from the day you drive the car off the showroom floor."

This is not entirely true. Many of the engines you mention are designed for use with premium lubricants, a result of the tight tolerances and lubrication requirements. The Corvette is an interesting example. Originally the current Vette was equipped with conventional oil. However, after many engine siezures while driving them on and off the transport to the dealers, it was determined a slicker lubricant was required to resolve this. The engine was simply too tight. Thus, the Vette was then factory filled with Mobile 1. All engines have a break-in period. The issue is whether there are any special requirements during this time. All contact surfaces must wear to mate. A little extra friction, when allowable, goes along way in helping this. You don't have to wait to change to synthetic, however there is a ton of data which shows that (1) todays conventional oils are very good and safe for your engine, and (2) waiting a change interval or two allows for faster, more thorough break-in, thus better fuel economy and performance in the long run. To each his own, however I have seen the data first hand, and it is pretty conclusive.

 

My last two cars were Audi A4s, each with the 1.8T four cylinder turbo charged engine. The 2000 A4 called for 5,000 mile oil change intervals, the 2002 A4 called for 10,000 mile oil change intervals. I was very skeptical and was damned if I would leave dyno oil in for that long.

I did more research on this subject than I've ever done on anything that was not engineering work related.

To make a long story short, my dealership put in Mobil 1 SuperSyn at 5,000 miles at no charge to me (they too were skeptical). After switching to the Mobil 1, the mileage in my car increased by a little over 1 mpg to 26.8 mpg. From that point forth I had my oil changed at 10,000 mile intervals. Later, after further research, I switched over to Kendall GT-1 Synthetic (probably overkill).

In the Prius I don't think the engine has to work hard enough to warrant the use of synthetic oil, and the oil change frequency is reasonable. On the other hand, if I can get that same 4% (2 mpg in this case) increase in gas mileage with this car as I got with the Audi, then the switch to synthetic certainly makes sense.

Before writing this I went out and checked my oil again (I have 4,400 miles on the car and will get my first oil change soon). The oil still reads full with no indication of any oil burned or consumed, and the oil still has that clean, new oil look.

Actually, the greatest concern I have with having my oil changed is the possibility of overfill (they fill it with a hoze coming from a large storage tank). If the oil is overfilled in any internal combustion engine, the oil will froth and the result will be poor lubrication of critical components. For that reason alone, as long as I'm the one who provides the 4 quarts of oil, the most they can overfill is 1/10 th of a quart (oil change with filter requires 3.9 quarts in the Prius).

Anyhow, I'll be switching over, probably to Mobil 1 5W-30 here in a couple of weeks. I'm excited at the prospect of even higher gas mileage yet.

Ken

 

It's easy to avoid an overfill. The maximum capacity including filter (that is, to the "full" mark on the dipstick) is 3.9 quarts; the minimum capacity with filter (that is, just enough oil to reach the "add" mark on the dipstick) is 2.3 quarts. This is documented in the owner's manual but, annoyingly, not all on one page. So give the oil change tech 3 full quart bottles of your oil, check the level yourself immediately after and top it off if needed from a fourth bottle.

For that matter, 3 quarts puts it nearly midway between the add and full marks, so strictly speaking it shouldn't need topping off at all.

 

I just changed my own oil and went with Mobil 1 5W-30. When I called toyota to schedule a tire rotation and told them I don't need the oil changed because I already did it, they said they don't recommend people doing the oil change themselves. I think that is bogus because it doesn't take a genius to change the oil. Has anyone else heard of Toyota not recommending a owner change their own oil?

 

Given some of the horror stories of others who had their Prius oil change by dealer service centers, as posted in other PriusChat threads, I would rather change the oil myself!

 

To summarize, if for whatever reason you want to use synthetic oil in your Prius, go ahead and do it; it won't harm the engine. If you prefer to use conventional oil, go ahead and do that too; it won't harm the engine either (after all that's what Toyota puts in the engine to begin with).

 

I'd still like to know if there's any scientific evidence of the oft-repeated claim that synthetic results in better gas mileage. A few people reporting on their own mileage is interesting but hardly scientific, as there are no controls on other factors. My gas mileage fluctuates more from one tank to the next than the suggested improvement attributed to synthetic oil. It is also improving steadily as our weather marches snail-paced toward summer.

 

Daniel,

I was also a doubter for many years. Its true that I believe that I saw definite improvement in fuel economy over an eight year period when I worked in field service (minimum 50,000 miles a year). However that was hardly scientific since the pool was too small. I don't expect to convince anyone else on my personal data alone.

For starters, how about this link at Royal Purple. They quote independent studies. This makes it easy enough for you to pick up the phone and call these entities to see if they really got these results.

Enjoy,
BobLo

http://www.royalpurple.com/techrp/summary.html

Here's one where the EPA clearly states that there is a 3% gain in fuel economy for delivery fleets. (Warning: PDF download)
www.epa.gov/smartway/documents/lowviscositylubes.pdf

 

I switched at my 5K Service. I'll let you know the results.

Of course I had the 40D done, it's getting warmer, and the car is breaking any, but I'm sure any mileage increase will be totally due to the Syn Oil