using 5w30 synthetic...would it be logical to use 10w30 to possibly slow the oil usage?? its not leaking on the floor...just burning i believe. 133,000 miles... i use the larger oil filter always..change the oil every 6k..add a few quarts in between

Yeah, you can do that but you are better of finding out where you are losing oil. Also, you might have to switch back to 5w30 when winter comes since you are in NJ.

Also, I am not sure why you are changing the oil @ 6k....I change mine every 3K. I change every 3K not because the oil breaks down, but because particles get into the engine through the air intake. If you don't get rid of them by changing the oil, then they cause microscopic damage which increases the tolerances between the parts in your engine. This might be why you are losing so much oil.....

As stated above I would check to find out why you are the burning that much oil. Are you adding oil within the 3,000 miles or after? I use Royal Purple oil and their filter. I change my oil every 3,000 miles even though its synthetic. I also have over 100,000 miles on my car.

hmmmm, well the 3.5 motors are known for oil burning, might find a selected few who dont have that problem with their 3.5. but ask around and most people will agree that those motors eat oil. i thought u had to use 10w30 oil. i tried 5w30 and my engine had a ticking sound, thought my motor was messed up. so i switched back to 10w30, smooth. try changing your oil more often even though you use syn, like Ram, i use syn oil, but i change every 3k

um well first of all it wont matter even if you used 15W30
the 5W you see is the cold temp viscosity when the engine cranks then when it warms up it goes to being a 30 weight
So if you want a heavier oil you need to look at 5W40 NOT 10W30
Also what kind of oil are you using
Just to point one more fact Mobil 1 is not a true synthetic base its a hydrocracked group III type

Forgot one thing, Why are you changing at 6K?
I change mine before 3K and thats with me using German Castrol [not regular ones you find at autozone] Its made in germany and yes true IV base

I had the same issue. Now I use Mobile 1 0w40 no more burning of oil as of yet. The vq35de is known for this issue and well changing the weight won't fix the problem just temp ease your mind a bit knowing you won't run out of oil as fast. Also like the guy above said doesn't matter if you change to 10w30, the 10 is for weather and the 30 is for weight. 10 is used in warm/ hot climates. 5 is for colder climates and 0 is for freezing climates. all have a temp range. 0 has the best range. Also the manual says you can use 5w30, 10w30 and Nissan service rep told me to try a heavier weight oil and see if it stops the burning.

I use GC and change my oil every 5k, my used oil analysis says my engine is strong

Which is the German Castrol? Is it the 0W-30? How can you tell it appart from the stuff you buy at Autzone and places like that?

GC will say on the back
Made in Germany
and in the front it says
European Formula

Apart from European Formula on the front and made in Germany on the back, it's 0w30, if you buy 5w30 it's made in the USA

You're prob. better off trying a high-mileage variant rather than changing the viscosity rating....

I experimented with M1 high mileage variant during one 5k OCI, with limited (less-burning) results.
But - I'm thinking of trying it again. Heck, what do I have to lose?!?!?

I'm STILL burning about 1-1.5 qts every 3k miles or less.
Nissan would NOT help me, but they DID warranty change my rear valve cover due to leaking.
Didn't help.
Compression test was GOOD -- so I'm just gonna dump oil in it until it BLOWS!

...thus the saga continues...

SURE wish I knew where ALL that oil was going to>!!?!?!?!?!?

gr

Tell them to do a leak down test

Yeah - i know...they convinced me that I didn't need one last time.
I have to be honest and say -- the mechanic WAS very honest. Just a kid.

But now I'm thinking that I should have done that.

i still have some of my ext. warranty left -- i think I'm going to try and get them to honour it.

gr