GC isnt the cure all end all of motor oil. some people engines dont like it like a 4.6 ford engine. I would ask did the engine get louder or the same as with M-1? 2 how long have yo uhad the GC in? 3 the sound is it valve chatter or what?
Dark Jedi 1) same as with M1. 2) in for about 3 days.
3) normal valvetrain sound. After remembering back to the summer i remember that synpower did quiet the motor down but i went back to M1 because it was my usual oil. The synpower was on sale at pepboys, that's the only reason.
I switched from dino at 11,000 miles to mobil1. I used valvoline synpower once when mobil1 was out and it did quiet down the mechanical sound of the motor. I tried gc and so far i havn't noticed any quieting affect and the motor felt somewhat sluggish. It has smoothed out some the past week. I will go 5000 miles and do an UOA to see if i will continue.
When you say timing chain rattle do you mean the sound you hear when you are at 3/4 to full throttle as the revs climb? Kind of a harmonic thing? I did not notice it with the mobil1 but i have it now.
I have a VQ-30 in my '97 Mazima. I ran Mobil 1 5w30 twice for about 4800 miles each time before getting UOA's. Both UOA's showed very elevated lead, and elevated iron. Other wear metals were normal. No fuel dilution, no AF, low solubles, etc. Just the spiked lead (up to 60 I think), and iron in the 20's. This was at about 78,000 miles (now at 109,000), and I have since ditched the Mobil 1 in favor of Castrol GTX with 3000 mile OCI's. I haven't gotten a UOA since, but I can honestly say my engine was louder with the Mobil 1 5w30 than with GTX. I have just changed with some GC (green), and will do a UOA at 3000 miles with it. I can easily tell my engine is quieter and smoother, to the point that I almost cranked it while waiting at a light (thank *** for tachs. If I hadn't looked at it, I would have cranked away). Anyways, rumor has it the VQ's like thicker oils. Mobil 1 5w30 is well-known to be very thin for 30 wt. And GC is a thick 30 wt. This could explain my observation, and also elevated bearing wear with Mobil 1.
On a related note, have you seen the European viscosity chart for the '97 Nissan Maxima sold in Europe? I had pasted a link to it in a thread in this forum here: http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=51;t=000692;p=2 Much different than my US copy which recommends 5w30 all year round. This seems to further validate the point that the VQ likes thicker oils.
Depending on my upcoming UOA with GC, I am inclined to try a 15w40 next run, as my ambient temps in Louisiana run from about 25*F (couple days per winter) to over 100*F (almost 4 weeks straight last summer).
Just some food for thought with your VQ.
The weather here in chicago has been much warmer than average for most of the winter. The MPG loss of about 5mpg has led me to believe that GC at least in my situation may be better in summer. I will switch when it's time to change oil.
Changed to synpower 5w30. Motor seems to rev faster and MPG is up noticably after 1 week of driving with Valvoline. UOA on the gc will tell me how it did. I think i will go back to GC when spring/summer hits. I had already picked up 5 quarts of gc but then decided to go synpower.
All this talk of a mpg reduction is interesting because I have experienced stability to a slight increase in MPG in my Taurus 3.0L. The Audi has always had 0W-30 (beginning with factory fill) so I have no way to make a judgement on it.
It could be all circumstantial that caused the 5mpg drop. All i can say is the weather here in the chicago burbs has been well above average. My focus has gained MPG cause of the warmup and my wifes altima has lost. I put synpower 5w30 in last week and the mpg average is just under our summer average in just one tankfull. Like i said it could all be circumstantial but i don't know. I will use GC in the summer, you guys have me convinced but the winter i will not.