From, "Synthetic Oil: Rx for Long Engine Life"
http://www.mr2.com/TEXT/synth_oil.txt

"On the other end of the thermal spectrum, synthetic oils are also
renowned for their high-temperature thermal stability. Superior
high-temp stability ensures and engine lubricant's capacity to protect
vital engine components during very-high-temperature operation, such as
hot summer driving, sustained high-speed driving, repetitious stop and
go metropolitan driving, driving in mountainous terrain, pulling a
trailer, or any driving with a small harder-working piston or rotary
engine. Underhood temperatures also take a quantum leap with the use of
power options, especially air conditioning, and because of emissions
devices and emissions-related engine redesign. It is important to note
that, even though the dash gauge may register only a 200F or so
water/coolant temperature, the temperature of the sump and of all the
assorted bearing surfaces significantly exceed the water temperature,
and often surpass 500F on the piston ring and cylinder wall areas.
These high-temperature surfaces serve to rapidly decompose petroleum oil
and additives, as well as contribute to their shorter service life,
while the synthetic is largely unaffected. Beyond the protection
afforded an engine during these particular instances of high-operating
temperatures, high-temp thermal stability moreover permits an engine
oil to deliver overall extended service life (significantly longer drain
intervals) in all driving conditions, because it prevents the phenomenon
of sludge and carbon deposit formations on critical engine parts
(valves, valve guides, oil channels, lifter assemblies, piston rings, et
al.) due to oil thickening, a problem commonly attributable to petroleum
oil breakdown at high temperature. As these deposits accumulate in the
oil circulatory system, oil flow drops, thus accelerating engine wear.
To the user of synthetics, the benefits are (1) reduced wear of critical
engine components; (2) significantly reduced sludge and varnish... a
cleaner engine; (3) reduced engine drag due to uniform viscosity; and
(4) increased fuel economy due to reduced component wear. "

......

The remarkable ability of synthetic oils to reduce internal operating
temperatures is far too important to ignore, since high operating
temperatures contribute directly to premature failure of mechanical
components and gaskets and seals. Coolant (i.e. water/antifreeze) cools
only the upper regions of an engine. The task of cooling the crankshaft,
main and connecting rod bearings, the timing gear and chain, the
camshaft and its bearings, and numerous other components must borne
entirely by the oil. There are three identifiable reasons why
synthetics do a better job of cooling an engine: (1) Because of both the
oil's lubricity (slipperiness) and it's stable viscosity, less
friction-- and thus less heat-- is generated in the first place; (2) The
molecular structure of the oil itself is designed to more efficiently
transfer heat, even compared against the thermal conductivity properties
(ability to absorb and dissipate heat) of an identical-viscosity
petroleum oil; and (3) As mentioned in the preceding paragraph, the more
rapid oil flow of these lower-viscosity synthetics contributes
significantly to the efficient transfer and dissipation of heat.
Because of all these factors, oil-temperature decreases of from 20F to
50F are quite common with the use of synthetic oil. One might even say
that the heat-reduction properties of synthetics are synergistic...by
helping to reduce its own temperature, the synthetic oil is
simultaneously enhancing the lubricant's overall performance
characteristics."

Steve - 21 year independent AMSOIL Synthetic Lubricants Dealer

 

Has anyone here installed an oil temperature gauge on their car, so they can see the engine temperature reductions with their own eyes? Curious.


Steve - 22 year independent AMSOIL Synthetic Lubricants Dealer

 

FI people should have oil temp gauges.

 

I agree. Anyone that wants to monitor what is really going on inside the engine should have an oil temperature gauge. Coolant temperatures and engine/oil temperatures are two different things.


Steve - 22 year independent AMSOIL Synthetic Lubricants Dealer

 

mine reaches 220 when im some what getting on it, but when i race people it can go up to around 240 degrees. i havent seen it past 240 even when im pushing it hard.

 

On this topic, I purchased an infrared temperature gun that provided very eye-opening data as to the engine temperature reductions when using AMSOIL synthetic motor oil vs petroleum motor oil. I will dig up that data and post it as soon as possible.


Steve - 22 year independent AMSOIL Synthetic Lubricants Dealer

 

Unfortunately the G35 has narrow lead free bearings [due to new EU regulations] which are 5 times more temperature sensitive than old wider leaded bearings [engines prior to 2002]
I would avoid any oil temp in sump above 220-225F as the bearings may be 50-80F hotter.

People will learn it is expensive to mistreat these lead free bearings.

http://www.enginebuildermag.com/Arti...ng_trends.aspx

 

Hello Q45tech. That is a very interesting observation you made and I thank you for the contribution. I saved the link you shared to my favorite places. Engines are changing rapidly and motorists would do well to keep up with these changes and alter their maintenance practices they have with their engines, accordingly. Doing so could save thousands of dollars.

With todays vehicles, replacement engines many times cost $5,000 +++, it is yet another valid reason to use the best performing/protecting oil possible, which is a high quality synthetic oil, of course.

$5,000 + engine....$1.50 per qt. oil to, "protect", that investment? It doesn't seem to add up. The engine for my own vehicle costs $11,000 to replace, and that's just the engine, not including labor! Using inexpensive oil is a false economy, in my opinion, regardless of how often it is changed or not. I think it's penny wise and pound foolish to use inexpensive oils in todays vehicles. Comparatively lower performing petroleum oils have not been in any of my vehicles or equipment for 22 years. I only use AMSOIL synthetic oils and over those 22 years it has saved me thousands of dollars in reduced maintenance costs and fuel costs, not to mention potentially saving several engines from replacement and the huge money that saved me.

Film strength is how much pressure it takes to force out a film of oil from between two pieces of metal and have resulting metal-to-metal wear. Even the best petroleum oils have a film strength of about 500 psi. With AMSOIL synthetic motor oils, film strength is up to over 3,000 psi! It's a quantum leap forward in engine lubrication and protection. Money well spent in my opinion, no matter which of the higher performing true synthetic oil brands a motorist uses. Have an oil filter punctured, or an engine overheat, or that long vacation trip in hot weather loaded down with occupants and their cargo, hauling a boat on a hot day, high rpm performance driving/racing, or what have you, any of these situations can stress a lower performing oil to its limits and allow resulting engine wear/damage. The extra insurance a high quality synthetic oil offers to an engine and the motorists wallet is money well spent in my opinion. Over the years, I've had more than one instance where using AMSOIL synthetic motor oil has saved my engine and thousands of dollars.

 

Steve, i was just curious if you have any input regarding dino oil vs. synthetic on the VQ35DE? I have heard, from many sources, that these engines prefer non-synthetic, both from members on this board and others, and several techs and SA's at the dealership. I have heard of people with oil consumption issues reduced oil use significantly by switching from synthetic back to conventional. Also every time i have brought the car to the dealer they urged me not to use synthetic. I am just curious. I have used Amsoil many times in my BMW's and have been very pleased with it, BTW.

 

Hello manbeer. I haven't heard this one before and an Internet search didn't reveal any information. The only thing I can guess at, is ignorance. Even to this day, there are a surprising number of people who should know better, who know precious little about oils in general and synthetic oils in particular. There is no reason not to use a superior performing lubricant in your engine. There is nothing magical about synthetic oils. They do everything a petroleum oil does, just better. In fact, my Internet search revealed many, many people using synthetic oil in the very engine you refer to, with superior results. Ditto in this forum.

Might want to ask these doom and gloomers specifically why they are making this anti-recommendation regarding superior oils. Ask them to show you something in writing, a technical service bulletin, etc. I wouldn't be surprised if you don't get consistent answers from any of them, but instead repetitions of old wives tales. Amazing that this persists in the year of 2008, but sadly, it does.

Keep in mind, the vast majority of automotive technicians, (and at my auto center, I work with them every day), are wrench turners. They usually don't read anything and keep up to date. But just because they can turn a wrench, take out an old, worn-out part and replace it with a new one, doesn't somehow mean they have knowledge or even up to date knowledge at that. There are exeptions of course, and one of them is an automotive technician who posted in this very thread regarding the elimination of lead in bearing materials and why that is a relevant factor in trying to keep engine temperatures down with the use of synthetic oils. A very sharp observation and this technician clearly is very intelligent and keeps up to date, by reading, not turning wrenches.

 

here a a couple threads i found related to dealers that don't recommend synthetic. I know that an relevant explanation is not provided but just so you have seen what i have:

https://g35driver.com/forums/engine-...synthetic.html

https://g35driver.com/forums/engine-...commended.html

https://g35driver.com/forums/engine-...commended.html

I know that Infiniti will now be voiding warranty claims on any of their newer cars equipped with VVEL ('08+ G37, FX50, etc)if the Nissan/Infiniti VVEL oil is not used. This oil is not a synthetic but rather a conventional oil with additives.

 

I have been told this as well from a Nissan Dealership perfomance division. The service manager stated that synthetic oils go right through the piston rings and causes the oil to burn off and he recommended that I only put regular oil. Needless to say I still put synthetic because synthetic oil is not thinner but just has better viscosity than conventional oil so it should lubricate the internal moving parts better. I don't see why he would say this if they have not been told so from Nissan Corp as it does them no justice which oil a customer chooses to use.

 

+1, there are many cars that don't take to synthetic well, the subaru STi being one of them. I have had more than a few friends who had major oil consumption issues and when taken to the dealer the dealer recommended switching back to dino, problem solved. It may lubricate better, but it will also burn and not stay with the engine like dino.