Z Owners, check your oil, post mileage and how far "down" it is...

davidyan

Here are some thoughts concerning oil burning:

Variable Valve Timing:
I have noticed that cars with variable valve timing and lift tend to use a little more oil than cars without however. I also have a 00 Celica GTS that uses something called VVTL-I using the oil pressure to control the intake cam timing position and lift function. It burns about 1 quart per 1000 miles. I've accepted that its part of the cars normal operation. I have great compression in all cylinders. It takes much more oil pressure to operate an engine with variable valve timing.

Oil Temps and Oil Burning:
Our cars have a tendency to run high oil temps. Higher oil temps mean that the oil will burnoff a little bit. Even if you're one of the lucky people who don't get above 220F, its still hotter than most cars. High RPM driving, tight engine clearances, and high oil pressure combined will result in higher temps. 370Z owners deal with all three.

Oil Capacity and Oil Burning:
The standard rule of thumb that auto techs and repair manuals have been citing is that up to 1 quart per 1000 miles is normal. I would tend to think this is too general of a rule. If your car has a 3.5 quart capacity, one quart per 1000 miles would seem significant. For a large V8 with an 8.5 quart capacity, 1 quart usage over 1K wouldn't be.

Also, that standard 1qt/1K mi rule of thumb came out decades ago when engines were a lot bigger than they are today and used more oil. I remember seeing that rule of thumb one of my old auto shop teachers 1970's textbooks that he had lying on the shelf. It surprises me that the auto industry hasn't updated their recommendation based on newer engine designs, oil capacities, etc. Less warranty claims?