Got a new 2005 6th gen., and put in synthetic oil at the first oil change (1k miles). The dealer later said that was too soon to make the switch because you have to give the engine seals a chance to set. I said "Good thing I'm leasing."

What's the story? Is there really a reason to wait, or was the dealer BSing me?

 

No, it's fine to put synthetic in a new car. He's BSing you about the seals.
Some high end cars come factory filled with synthetic, and call for it at every change thereafter.

 

I think it depends on who you talk to. Mobil says that this used to be true, but not anymore. According to lightonthehill, many Nissan engineers recommended waiting until ~20K to make the switch (but I think this was for an older Nissan engine). I kind of split the difference and went with 8K. I'm at 34.5K now, and it runs great (although it's probably way too see any issues with this).

Good luck!

 

I changed engine oil and ATF to synthetics at the 1000 mile point and have done so on several new cars that I have owned without issue. My Max currently has 80K...it runs better than new and doesn't leak/seep/use a drop of oil between 6-month (9-10K change intervals).

A conservative time to change is at the first normally scheduled oil change.

 

The blurb I read from the Nissan engineers between two and three years ago (the 6th gen had only been out a few months at the time) was that the synthetic oil was TOO GOOD as a lubricant, and prevented the very slight bit of wear/adjustment of engine parts necessary to make everything fit together perfectly.

Since these folks are engineers, and I am not, I took their word for this. I will convert at 20K.

From personal experience, I know the engine will operate fine with either oil. I put over 200,000 miles on each of my first two Maximas (early gens) on dino oil with no problems.

I look at it this way:

The Nissan engineers' vested interest in this situation is to have the engine last as long as possible and operate as efficiently as possible.

Mobil's vested interest is to sell as much expensive synthetic oil as possible.

I know who's word I took. But 'to each his own'.

 

I agree with light's post above. The synthetic is too good a lubricant. I changed to Mobil 1 at 7,500 miles and if I had a chance to redo this change, would wait until 15,000 miles. My VQ burns about a quart between oil changes which I do every 7,500 miles with synthetic. I attribute this to the rings not seating in completely before I switched to Mobil 1. (I was changing every 3750 miles with dino oil.)

 

The rings were seated long before 7500 miles. I talked to a few engine builders and did quite alot of research on this subject before I built my last couple engines. All the "expert" engine builders did agree NOT to break in the new engine with synthetic oil. I got slightly differing 'break in' mileage form some of the builders, all fell between 100 miles to 1000 miles.
Also, it's off topic but engine rpm cycling and not running at extended higher rpm periods is very important in the break in period.
So, I deduce it to be perfectly fine to switch to synthetic after the first oil change. 3750 miles.

 

Nissan recommends waiting before going to synthetic. I would follow their recommendations -- not certain I would wait as long as 20 K miles, but at least somewhere between 7.5 K and 15 K miles. They designed the engine and know how best to take care of it -- absent any definitive information to the contrary (which I've not heard, yet).

 

I was also wondering 'WHO' at Nissan says to wait to change to synthetic? And, how many miles does this Nissan person say to wait?
Also, I don't believe that anyone at Nissan wants their products to last as long as possible, they need to keep selling products, but I must say that the VQ engine is one of the longest lasting there is.
I also don't think that Silvermax's engine should be burning a quart every 7500 mi. Neither of my VQ's have burned that much oil and both had higher mileage.....
Well, just trying to liven up the Fluids and Lubricant area, it's kind of dying out in here.

 

If this was my car I would get the synthetic oil out of there ASAP and use Castrol GTX 5w30 oil until about 15,000 miles.

 

I guess you missed the Sticky http://forums.maxima.org/showthread.php?t=221394

The 1st post is the most important, I have dino Mobil Drive Clean in the Max and will switch to synthetic at 10k