Okay. So I did tons of research and I finally decided to go with Amsoil 0W-30 100% Synthetic oil.

My question is this: It's been beaten into our heads that we change the oil every 3,000 miles. Amsoil claims to change this specific oil every 35,000 miles or 1 year whichever is sooner(under normal driving conditions) and 17,500 or 1 year whichever is sooner(under severe driving conditions). I also have a Amsoil EA oil filter and it claims it needs to be changed every 25,000 miles or every oil change. So, the big question is: When do I change my oil? Common sense tells me to do it every 17,500 to be safe? But, then there's that every 3,000 miles theory lerking in the back of my head!!!

Anyone please feel free to drop there two cents in...

 

I use the same oil and change it every 3k relgiously. I don't see how you can go 20k+ miles on a single oil change.

 

If you want to be conservative, use Amsoil and filter and change every 5000 miles. Several members on here change at 7500, I change at 10,000km which is about 6200 miles.

 

IMHO, the best answer is "It depends".

My wife and I drive roughly 9-10 miles each way to work, with occassional 10+ mile trips. We're in Northern NJ and still in warranty. So basically we're in that fuzzy zone between severe and normal service.

Given above, I change the oil every 6 months (Nov. and May of every year) or 7500 miles, which ever comes first. The idea of changing oil in the middle of the winter does not get me excited, hence the 6 month interval. Also, since we drive roughly 9000-10000 miles per year, we in general never hit that 7500 mile limit..

I'll assume you're out of warranty. If I lived in a climate like Florida, Texas, Arizona, etc., I'd do an UOA at 5000 miles and extend the drain interval based on the UOA or to a point where you're comfortable, since you don't have to worry about changing oil when it's below freezing outside.

Personally, given our 5 quart (or so) sump, I just don't see any oil lasting 35K miles/1 year or 17.5K miles/1 year. I believe Mercedes Benz now dictates that the oil on their cars get changed 1 year or based on the oil life indicator, which ever comes first, allegedly after having some oil issues after solely depending on the oil life indicators. Note that most, if not all of MB's have large oil sumps, 8-9 quarts, running Mobil1 0w-40.

My 2 cents.

 

Thanks every1 for all of the input so far. I think I am just going to be very observant of the oil consumption and appearance. If the oil stays its relatively new color I'll extend my interval, and vice versa if the oil looks like $hit.
I love having the comfort of using synthetic oil in my motor, but not too excited about the price...so if I can make it 6,000 miles, which would be two typical oil changes, I can talk sense into my wife. But, if I do it every 3,000 miles, my wife will probably beat my ***. lmao BTW I live in MN and I hate winter oil changes!

 

The oil turns pretty dark really fast so I wouldn't use the color as an indicator. If you are easy on the engine and do alot of highway miles I wouldn't go more than 10k miles.

 

Yeah, I suppose not. I guess it was just wishful thinking. I think I'm going to shoot for 6k miles and change it. That way its a little more affordable, while not risking any harm to the motor.

 

As mentioned, oil coloration isn't a definitive indicator for oil condition. The best would be an UOA.

Question though, why Amsoil? Did you check out GC? It's far cheaper than Amsoil and very good in the VQ engine. I'm running gold GC right now in my engine and it's running very smooth.

 

I've heard very good things about Amsoil. I checked out some other oils and ultimately decided on Amsoil, mainly for the rep on their 0w-30 syn oil. How long are you running the gold GC in ur motor before you swap it out? and I have no idea what an UOA is? Im guessing it messures oil particles or something?

 

i just ordered this oil and their filter for my car. i heard it was the best for FI so im going to give it a whirl

 

Cut and paste from the G35 Factory Service Manual:

SAE Viscosity Number ALS0006I
GASOLINE ENGINE OIL
SAE 5W-30 viscosity oil is preferred for all temperatures. SAE
10W-30 and 10W-40 viscosity oil may be used if the ambient
temperature is above -18°C(0°F)

A major auto company spends millions of dollars and untold hours developing an engine. Based on this research and development, guys in white lab coats with engineering degrees specify a oil that will maximize engine longevity and performance. Then, after spending twenty to forty thousand dollars on a G35, some think it is a good idea not to follow oil specified by Nissan. Incredible..

0w-30 Amsoil? Have fun with your science experiment. My money is on the guys in the lab coats.

Not trying to start a flame war, I am trying to make a point- Stick with with Nissan's recomendations...

 

I should add that if you are FI or have major internal changes (pistons, cams, springs etc)- the statements in my last post might not apply. When you make these changes (which was never factored by Nissan) you need to be aware that today's passenger car motor oils are formulated to be compatible with a street car's emission control equipment, and Federal EPA (idiots) requirements which have forced oil manufacturers to reduce amounts of anti-wear additives like Zinc, Phosphorus and Sulfur in API rated engine oils. While this is fine and is good for your street car, it could be very bad news for a highly modified engine. You need to look into a true racing oil.

I probably should qualify that my statements are based on my experience in owning a company that has built racing engines for sprint cars, late models, and midgets for over twenty years. I do not have a engineering degree (HR management)- However we build 900 hp NA all aluminum engines based on Chevy small block architecture that spin at 8000 to 9000 rpms, needless to say, we have learned a few things about engine oil.

 

On a Mobile 1 I did every 3k

With German Castrol I'mmona do every 5k.

I wanna grow old together with my VQ.

 

Amen brother!

 

+1, but I'm sticking with my 0W-30. I know of a few people on here that will swear by it too.