So I finally got around to 1000 miles (987 to be exact) and I changed oil, though not the filter to Castrol GTX 5W-30. Cuz I remember reading about letting the engine break in more before putting in synthetic. And now I swear the engine response seems slower, (when the engine is cold, and the oil is presumably thicker?) Well I don't know if its just me... But I don't think I'm going to stick with it. I'll probably change again at 1500 miles, along with a filter, but are there any recommendations on non-synthetic oil?

Black / Black 2004 GcoupeMT. Premium. Splash Guardz.

 

uh....why did you change the oil?

 

because one of the oil analysis reports on FA for a new G35 showed that the oil at 1000 miles was in the condition of oil with 3000 miles on it.

The filter could have used a change too, but you wont do any harm by leaving it on as you did.

Mobil1 DriveClean is a good dino oil. I went with this before switching to Mobil1 syn at 5K.


bs g35c lth/prem

 

Leaving the old filter on was not a good idea:

1. You leave in a half quart or more of dirty oil.

2. A dirty oil filter wont flow as much as a clean one, and some loose particles may contaminate your clean oil.

3. Oil additive packages are not the same, never, ever mix oil from two manufacturers. When you left old oil in your old filter, you mixed oils.

4. A good oil filter is less than $10.00, why in heck wouldn't you change it?????

Lou

 

In hindsight, it was a really bad idea, and I'm tempted to go change my oil again right now.. The thing is, I didn't have time to go to the Infiniti dealer to pick up OEM oil filters. Heh, don't laugh, but I like to keep all that stuff OEM on my car.

Black / Black 2004 GcoupeMT. Premium. Splash Guardz.

 

lowrider,

Mixing oil from different manufacturers is not a problem, so long as they are both the same weight and rating.

Using your logic, you should NEVER change oil brands from the factory fill. Why? Because you will NEVER get all of the old oil out of the engine when changing your oil. It's impossible, so you WILL be mixing fresh oil with some old oil no matter what.....

 

I'm not going to argue with you. Residue in the oil pan is one thing, half a quart in the filter is another. Again, never mix oil from different manufacturers.

Lou

 

The owners manual says to use mineral based oil. Which means non-synthetic

 

Correct me if I'm wrong, but don't a lot of members here use synthetic?

Black / Black 2004 GcoupeMT. Premium. Splash Guardz.

 

Service manual does not specify non-synthetic. I've been using mobil 1 since 3k. As long as your synthetic meets the API grades below it is fine.

Recommended Fluids/Lubricants
With oil filter
change 5 qt
API Certification Mark*1
API grade SG/SH, Energy Conserving I & II or
API grade SJ or SL, Energy Conserving*1
ILSAC grade GF-I, GF-II & GF-III *1

SAE Viscosity Number
GASOLINE ENGINE OIL
SAE 5W-30 viscosity oil is preferred for all temperatures. SAE
10W-30 and 10W-40 viscosity oil may be used if the ambient
temperature is above -18C(0F)

 

ah never use that GTX crap. If your going to use Castro at least use the semi-syntec. I change my oil at 1000 miles too and the car felt different a lot smoother.

The GTX probably just has to wear in a little. Then the car will start feeling alive again.

Just change your oil by 3,000 to castro semi synthetic. Don't use full "real" synthetic (like Mobile1) till about 10,000. It seems like the G take a while to break in. It takes even longer if you baby the car.

BS G35C 6spd navi/aero/prem

 

GTX is better than its synthetic counterpart per blackstone labs test. GTX is one of the best dyno oils you can get.

 

Anyone thoughts - Going to change my oil at 5,000 miles ('03 G35c6mt) to a K&N filter and use Red Line Synthetic 10-30w oil. I've already had one oil change by dealer at 2,500 miles. Is this a good filter & oil combo? Thanks for your input.