What is a safe guess as to how many miles you can stretch out of an oil change. My car has been set on the 3,750 mile schedule and I just get whatever oil the Infiniti dealerships usually fill it with. My questions is that in about 3 weeks I will be going on a small road trip (1500mile roundtrip) but I am about 900 miles from my next "scheduled" change. Ill probably have 500 miles left by the time I leave. Do you think I can safely squeeze in the road trip, or should i change the oil beforehand? I would be at about 4,750 miles on same oil?

Thanks!

Yea I dont see how it would be that big of a deal, just never double the interval and you'll be ok.

You should be fine. Check your oil color and level before and during the trip. If it is really dark, then you should probably get a change, but you will probably see that your oil is a light to medium brown/amber.

Thats what i was thinking. Thanks for the responses!

after 4k on regular oil, the VQ tend to get alittle fuel dilution and might use alittle oil. This largely depends on your climate and conditions, varies between drivers and cars. You should take a qt with you and be sure to check the level on your last legs back. Adding 1/2-3/4 is normal and should be expected at 4500, especially after a few hours at highway speed/rpm. It will actually be helpful overall to bring the level back up. Too bad the dipstick sucks, but nonetheless, you dont want to lose too much. Remember bottom to top tick on the stick is 1 qt.

should not be a problem.... but why risk it? Just change the oil and be done with it.

You should be ok to leave it, but if it were me, I'd change it b4 going. My .02
C.

the interval is 7500 mi per the manual. Unless you meet the hard usage conditions like towing, frequent short trips, etc. Personally, i go around 6k miles on full synthetic and the blackstone lab tests seem to show that is fine with this engine using Mobil 1 full syn.