I don't know what's wrong. I have a VG 5spd. I change my oil every 3000 miles and I use Mobil 1 synthetic 10W30 and Nissan OEM filters. But about 1500 into the change, the oil is black, and half of it is gone. But there are no leaks, so I must assume that it is burning off somewhere. What would be the best things to check out.

 

bump

 

do u see smoke out of your tailpipe? blue smoke?
do u see oil in the coolant?

it can be a number of things.

 

NO oil in the coolant, or vice-versa. I think it's burning away some how.

 

Check for leaks

 

Valve guide seals

 

if that's the case he'll see smoke during start up...or the first few secs of it right? he said no smoke.

 

But I do get a lifter noise (tap,tap,tap,tap,tap) when I first startup for about 2-3 secs, then it goes away.