I wonder if it's OK to switch at 30K. I've read the oil bible that said you don't want to switch to synthetic oil after 20K unless you do a complete flush to clean out any residual accumulated from regular oil.

 

should be okay

 

Thats a buncha BS...!!
The synthetics and regular dino squeezins will mix, no prollem..

B well..

 

yes you can switch.. you will have no problems at all... no need to do a complete flush

 

Motul is an ester based lube which means it is highly detergent. The esters will dissolve any residues and take them into solution. This means that the first few Motul oil changes will have the oil turn black pretty quickly. This is especially true if you have been running dino since new.

I'm all for synthetics, but IMO the ester based oils are racing only and/or motorcycle use. The RPM and heat levels in a street VQ are far below what justifies esters. If you want a bulletproof oil for reasonable cost, use the Mobil1 TurboDiesel Truck.

Sounds crazy due to the name, but the stuff is full PAO unlike the other M1 and has a worldclass additive package. I have been using it up to 15K and have 90K on my G now with only 2-3 qts usage during that interval. Google it and read the tech sheet. Best value out there.

 

Haha 2-3 quarts usage, if our VQs were built right with better seals and valves they would burn 1/4 of a quart and that would be on your hands and drive way!

 

A qt. every 5K is normal. I dont know how much you use, but my motor has never been an oil hog. But I broke it in hard and fast, maybe thats the difference.

 

good and normal engines from other muanfacturers DO NOT BURN OIL. One quart burning every 5k is Infiniti jargon that is BS. No performance engine or any engine for that matter should burn oil. 1 quart per 3k miles is what they tell you at the dealership...to basically shove it and were not replacing your engine.

 

Yeah...dont even get me started on OC issues. Infiniti wont do crap unless you consume 1qt/1000 miles or worse.
Unlike Nissan that has finally admitted to OC issues with the Rev-up VQ and their TSB for the Z's back in Nov 2007.

I've heard and read Motul is not that good for our VQ's. Seen UOA's from VQ's on that stuff and the analysis not that good. Many better oils out there.
http://www.my350z.com/forum/showthread.php?t=258663

 

I disagree. ALL engines consume oil during normal operation. Some designs more than others, but they all do since components of the oil are volatile and the microthin film left on the cylinder wall gets burned off every cycle.

But I also agree that some VQ's going through more than 1 qt/3K is excessive. But that still does not mean that the motor is trashed and needs replacing as long as the compression leakdown and the cylinder variation is in spec.