I've spent a lot of the night searching this forum for answers to my questions and really haven't found much and what I have found has been pretty conflicting.

I've been using Mobil1 5W30 since I got my 06AT G35X. Actually recently started using the Extended Performance. I've read a fair amount of negative posts towards M1 and that it has decreased in quality and is not as good in our cars as other brands. Who knows if it's true or not but I'll probably switch to Castrol Edge Synthetic since that seems to get a lot of praise around here.

My real question is that I have been burning a little bit of oil in between changes. It seems as though I've burned a little over a quart since my last oil change ~4K miles ago (hard to really tell with that crappy dip stick). I read on here that changing to a 10W30 may help this consumption issue a bit and was looking for some opinions or hopefully even people who went through a similar issue.

I currently have about 64,000 miles on it.


Thanks!!!

 

Also, for people who do not have any oil consumption issues at all, have you or do you ever plan on changing from 5W30 to 10W30 at a certain mileage or will you just stick with what you've been using for the life of your car?

 

I used to use 10W30 in my G35, it seemed to help a little bit on the burning oil issue. It didn't completly eliminate it but I didn't have to add any at 5k oil change intervals. With the 5W30 I had to top off once at around 4k. I would still be down about a quart by the time I changed my oil. It's ok to use as long as you don't get freezing temps. Here in Hawaii is't always warm so no issues. From what I understand your gas mileage may go down a bit with 10W30 but it sure beats having to check the oil level all the time.

 

two concerns i know of...

climate and engine clearances

thinner oil is needed for colder climates and engine with tighter oil clearances.

 

From what I understand, the only real difference between 5W30 and 10W30 is the viscosity at start-up. As has been mentioned, if you live in a climate that never reaches freezing temperatures you should be fine using either one. Once the oil reaches normal operating temperatures their viscosity should be identical.

It really depends on when the oil is being consumed. If it's at start-up, the switch to the slightly thicker 10W might help. If it's during normal driving I don't see how it would make any difference at all seeing as both are 30 weight oils once they are warm.

Keep in mind that this is just the information I've gathered from doing my own research so take it for what it's worth. I actually plan to continue running 5W30 in the Summer and switch to 0W30 in the Winter. I have no noticeable oil consumption though.

 

^^ what he said here. If your oil burning is at startup, then 10w30 may help. If its burning after being warmed up, then 5w40 or 0w40 or whatever is what you want. Typically it's going to be happening after being warmed up because the oil is much thinner then.

As far as quality of the oil, Mobil 1 isn't the greatest with the exception of the 0w40. If you want a 0w30 oil I would use Castrol Euro formula. If you want 5w30, Pennzoil Platinum or Ultra are better.

 

i've been using mobil 1 5w30 w/o any problems, but i think for oil you can change the O-ring in the oil cooler and see if that helps?

 

Honestly I'm stumped on what to try next. I've read people suggesting to switch to conventional oil. I've read 10W30 10W40 and 0W40. I want to try a different oil from Mobil 1 5W30. What does anyone suggest that would have the highest probability of fixing my oil consumption issue?

Again, I have ~64,000 miles on my car. Not sure if the mileage would make a difference.

 

Seems like a 5W40 might be the most logical? That'll increase the viscosity of the oil which may help?

And for the record, I dont drive my car hard at all so I dont know if this makes a leak more likely or not.

 

Switching to conventional helped me and my sedan was consuming 1 qt per 400 mi.

 

use a thicker xw-30 like German Castrol 0w-30

or go with a thinner 40.. like M1 0w-40... both should help with your oil burning..

 

05 AWD A/T. A few things I have noticed with my car. I got it off lease and always serviced by Nissan with records. It had 136000 km on it. It had an oil change sticker from Nissan in the drivers side vanity mirror. I changed with Castrol GTX 10w30 and in 4000km no oil burn. Then I put in Castrol Syntec Synthetic blend 10w 30, and still no oil burning at 5000km this time. Then for winter I put in Syntec 5w30 and burnt half a litre in 4000km. First time my car burnt oil. I am giong back to Syntec 10w 30 for summer, and if I still burn oil I will go back to good ole 10w30 GTX. I put the pedal to the medal at least twice a day since I bought my car.

 

What are you going to go back to next winter?

 

^Agreed, well said

The hard truth is that the type of oil you use isn't going to fix a mechanical oil burning issue. The idea that it will always makes me laugh when I hear it from guys.

Is is possible to find an oil that seems to burn less? Yes, definately, but I'm sorry that I can't help point you to that specific oil.

Whan I can tell you from my research, is that 10w30 and 5w30 are not necessarily better/worse for burning oil because of the viscosity rating. They're different because 80% of 10w30 oils are designed for older engines with higher wear. It's not the actual viscosity that's different, but rather, the FORMULA/ingredients in the oil that are different. It's these characteristics that usually cause less/more oil burning depending on the catalyst involved, ie. compression, NOx, fuel, shear, etc. Depending on the specific cause, different oil formulas/additives will react differently.


You've got this completely backwards

40 weight is thicker than 30 weight.

If the car's burning it's oil when cold, and under high RPM's, as is most likely, Then the first number is the most important. 10w30 will slow consumption in this case. Keep in mind though, fi you're in cold climates, you're better putting oil in more often (letting it burn) and using the 0w30 or 5w30 that is recommended for your climate.



And Mobil one hasn't gotten worse, they just haven't gotten better fast enough, as such, they're no longer the "leader" in oil technology. There's other companies that have surpassed them. As such, Mobil 1 just isn't worth the money any more by comparison. That doesn't mean it's "no good"

 

^ I think he just means the Mobil 1 0w40 is a thin 40 weight oil, which it is