There are many posts on synthetic oil, but I haven't found one that succinctly responds to the following questions - perhaps this thread would make for would be a good FAQ !..

1) The 2007 G35 maintenance schedule does not mention synthetic oil - does its use violate the warranty?

2) If one of the advantages of synthetic oil is to extend maintenance intervals, then this means owners would NOT following the recommended intervals., Is that not a warranty concern?

3) What is the recommnded extended interval for syntehtic ? - is it every other normal oil change? Where would it say, given its not in the manual?

4) Are there certain criteria/driving habits which would be the deciding factors in whether or not one should switch to synthetic, or is it just a preference? The advantages quoted to date are such that they in essence apply to everyone , i.e. a higher shear strength, cleans and suspends dirt better, flows better at lower and higher temps, does not leave residue on engine components, will keep your engine cleaner internally, better protected, cheaper in the long run.

5) Is synthetic oil suitable for those of us in winter environments for half the year?

6) Is there a particular type or grade of syntehtic oil that is suggested for the G35 (coupe or sedan or AWD)?

7) When should one switch to synthetic oils..prior to first recommended oil change? … at the first recommend oil change? …after the first oil change?

8) Is there a recommended brand?

 

If a can of worms is opened in the middle of the forest, does it make a sound?

 

Just kidding, ThatsMyG. Everyone has an opinion about these; some are heated. I'll give you my angle.

 

Well for one, this topic has been discussed at length. And two, Mobil 1 is no longer synthetic.

 

There are different levels of Mobil 1. Standard, Synthetic Blend, and two grades of Fully Synthetic.

 

Search my friend. Read up on synthetic first on all the threads you can find and you will find all the answers to your questions. Its all there...Its been discussed in many threads.

Pure synthetic will cost you a pretty penny. Mobil 1 like Jeff92e state is no longer fully synthetic.

 

HAI109.... thats a sick avatar u got there

 

Thanks...I got it in one of these threads...I forget which one...

 

fist things first you shouldnt be using syn oil yet since your car is fairly new. Use good old regular dino oil so you can get the engine broken in properly. after 15k or so miles you can switch over to syn. I use german castrol or known as castrol syntec 0w30 it is a group iv oil and is fully synthetic. if you need any more info search around on this forum or check out the oil forums. good luck!

 

I'll take a crack at my advice, since I don't think will have any definite confirmed indisputable evidence to answer most of the questions:

1.) No it doesn't violate the warranty,

2.) It's recommended interval, not a required interval. and synthetic has it's own interval depending on quality and type.

3.) There is no general recommended interval, each oil has it's own interval and you need to follow that, so if you decide to use Mobil1 extended, then your interval is 15K miles, if you yous AMSOIL your interval is 25K miles or 1 year, which ever comes first, if you use standard Mobil1, I believe it's 7500mi or 6mo. so which ever oil you choose you need to follow that interval to keep the oil within specification.

4.) Synthetic performs better at all that you mentioned and about 400 other metrics... Dino oil has no single specification or situation where it outperforms synthetic. I've seen testing results that show synthetic oil with 20Kmiles has better lubricative properties and is cleaner then standard oil with 3Kmiles

5.) Absolutly, has nothing to do with the oil, temperatures are by oil weight, 5W30 is recommended for all-around... I think in extreme cold they recommend 0W30 because at cold temperatures it's more fluid, yet still maintains it's high temp of 30w.

6.) Oil is oil, so just how dino works fine, any synthetic that is 5w30 or 0w30 for cold weather will work. But on a personal level, I always say choose the best.

7.) This can be debated but I don't think this really matters at all, all highend sports cars come with synthetic right out of the gate, why should the G35 Crap the bed when it gets a shot of synthetic.. Some say that synthetic is so slick it can go right around gaskets so it's beter to use the sludgy dino oil until a good layer of cake forms so all your gaskets are packed with burnt dino... not sure how that's better, seems like there's no reasoning there... so common sense tells me your fine with Synthtic from mile uno!

Now this is very important, keep in mind that the car came filled with Dino, so on your first oil change, if you change out to synthetic which is rated at 15K miles, you need to have your next oil change at 3750 as originally recommended by the Dino oil, that's because there is remanants of the original oil still inside the system which "contaminates" the synthetic, it doesn't damage the synthetic, but that mixture is not going to have the same characteristics as pure synthetic, so the rule of thumb is just stick with the original 3750 for the first change.

8.) nope, no recommended brand. but if you Google amsoil, mobil1 for synthetic oil diagnostics... I think you'll see that Mobil1 (current generation) and Amsoil are always the best at impurities and quality of the oil after it's recommended interval, i.e. Mobil1 at 15K miles is still actually fantastic oil and could probably go to 30K. I'd say go mobil1 18 billion served can't be wrong

 

Where are you guys getting that Mobil 1 fully synthetic is not actually synthetic?

 

It's been discussed before...Mobil 1 changed their formula after they found out that Castrol Syn wasn't fully synthetic. Only German castrol was pure synthetic. Mobil1 sued Castrol stating that they are advertising full synthetic but lost the case so they changed their formula because full synthetic costs more to produce. I'll try to find the thread...

https://g35driver.com/forums/showthr...ghlight=mobil1

 

Is that why a lot of high end cars come with synthetic from the factory?

 

I covered a lot of this ground in my extensive searching, and FWIW I wound up choosing Amsoil (full synth) and Wix filters. Keep in mind I have no break-in period to worry about, so heed the 'first 3750' advice above.

 

I did search, but there are 231 threads on this topic with umpteen posts to each, so I thought it would be an idea to take stock and summarize. I pulled out some common questions and added some of my own, in the hope some conslusions could be drawn. I think it worked out perfectly, and its now succinclty summarized for the record, especially for those of us who are new to this.