So today I visited a local Nissan dealer for the first time to get my oil changed. I asked them to put my oil in the vehicle Castrol Synthec and service rep saoid the darnest thing. I quote " You know Nissan does not recommend Synthetic in these cars right" I'm like no but I've been using it a while on my previous 04G sedan. She mentions it affects the valve clearance. Anyone ever heard that?

 

When we bought our car used ( 2007 G35 ), the sales guy told us just to put regular oil in there, no need for synthetic, it was just a waste of money.

But then, when I got the car home, I drained it and filled it with synthetic oil, and when my wife was at the dealership for some warranty issue, they asked when she wanted to come in for an oil change, and she told them I did that, and they said why, since they put synthetic in there anyway?

Which I think is BS, they're not going to put synthetic in the used cars they are selling! Ahh... and that's why the wife and I hate dealers.

 

Although Nissan Corporate (online support) has at one time or another responded with similar comments about synthetic oils on certain models, i have yet to read one for the G.

If you look at the manual, their only requirement is that it meets the minimum standards. There is no mention of mineral or synthetic.

That said, you have to realize a lot of dealerships will use the most cost-efficient oil they can get their hands on, and will most often try to get you to use that.

 

Yea they won't just put synthetic in a used car, believe me I just bought this 07 CPO back in Nov with 30900 miles and the dealer didn't even do the entire 30K svc, they just did the cheap options. I ended up a month later having to change my belts and do radiator drain and flush. Nothing was wrong with the belts I just wanted it done since the car had 32K by then.

Yea I just want to know if thats true because i will stop buying synthetic, afterall there is no visible gain to using it anyway. Plus I haven't kept a car long enough to benefit from the extra cost of synthetic

 

Not all oils are made the same. Some dino oil's work better than some synthetic's, and vice versa. FWIW, i'm running Mobil 1 EP (synth) with excellent UOA results. My next change will have 9k miles on the oil's life.

 

I hear what ur saying, but they weren't trying to get me to buy their oil, they were asking me if I knew that Nissans doesn't recommend the use of synthetic. Like I said in my above post I see no benefit of using synthetic, it's just that I drank the synthetic Kool-Aid and thus have been using it for a little while. If Nissan doesn't recommend it then I will stop, regardless of what others may say. Nissan may have designed their vehicles to where synthetic could affect certain things, but I need to see that somewhere and the owners manual doesn't specify. That doesn't mean it doesn't exists.

 

My Infiniti/Nissan Dealer stocks Mobil 1 Synthetic besides the regular dino oil. They put Mobil 1 in my FX and used to put it in my G35.

 

I think that service rep is full of ****, and not the synthetic kind. I've seen excellent UOA's on the V36 with Amsoil synthetic.

 

^ LOL I thought so too but whatever.

I think what everyone is missing is the fact that tests may show great break-down or lack of in a specific oil. However that doesn't mean that the use of Synthetic oil doesn't affect something else, for instance her claim of it affecting valve clearance. How do you check that from your lab results after testing ur oil? You can't. So no-one looks beyond the lab results which just shows how a specific oil is holding up, that's it.!!

It's just food for thought here, I don't want to start any arguement of whether synthetics are good or bad. Every application is different. BMW comes from the factory with syntheitc, Infiniti doesn't, and that may be for a specific reason.

 

It also tells you how well the oil is affecting engine components by way of stray or elevated metals in the used oil, as well as how well your air filter is working, among other things.

It's hard to tell why certain manufacturers use certain things. With BMW, one could say they use synthetics because they include free oil changes that have 10k intervals and either (a) don't want to have to spend any more on those "free" changes or (b) they know synthetics last longer with those intervals.

Nissan has never stated that they don't recommend synthetics on our engines, neither have they put in writing that they only recommend dino oil.

Just putting that out there, feel free to use whatever you feel comfortable with.

edit: Have your service advisor worked with Honda's by any chance? Could explain her "explanation" of valve clearance issues.

 

Nah she worked for Infiniti before moving over to Nissan actually, so IDK. I will definitely research it some more. I have taken my previous G35 for 4 yrs to Infiniti dealer with my own oil (Mobil1 Syn) and was never told that, for that reason I'm super confused. I explained this to her also and she stated that the older model were different which i completely understand.

This is what I sent to Infiniti Corporate this morning. Will wait and post response:

Hello I have a 2007 G35 Sedan and received an oil change this morning from a local Nissan Dealer. I was told by the service rep that Infiniti doesn't recommend the use of Synthetic Oil in my vehicle. Please confirm this claim as I am still unable to verify such a claim.

For reference I was planning on using Mobil 1 5W 30 Synthrtic in my Sedan.

 

Syntec is fine it shows one of the best uoa's in the VQ



I Have been running it since may 09. There will never be an issue. The dealer just wants you to use their oil, btw syntec is mostly made up of highly refined mineral oil.

 

My take on this ... There is less margin to the dealership for synthetic oil so they push the dino. Service writers are paid on commision so they make more $ on selling cheap dino oil. Oil change intervals are also longer with synthetics so they lose the labor by doing fewer oil changes.

 

^ yea there's a lot a play here, and believe me I'm not just taking what they said with a grain of salt, on the other hand if its true I won't waste the money or it'll be just like putting premium gas in a Nissan sentra XE

 

Synthetic should not be used when the vehicle is new because it will prevent the engine from wearing in correctly. Once worn in synthetic will help you engine live a longer life.

The best use of synthetic oils if for use in extreme conditions, regular oil is fine for all else as long as you change it regularly and use a good quality oil filter. Don't use fram, they are crap.

On valve clearances even with hydraulic lifters I also call BS. It is very important to keep your oil clean for hydraulic lifters to work properly, get them dirty and they will click and pound on your valve train causing more problems. On the G35 their is no hydraulic lifters, the cam pushes directly on valve so the oil cannot affect the valve lash except by allowing wear to happen.