my car absolutely eats through oil. blows a lot of smoke when i get on it too. I don't know what the problem is..

 

i'm still lost what's better of the 3

castrol edge with kn filter
mobile 1 with mobile filter
royal purple with kn filter

all 10w30 which r considered the most beneficial for our cars?

 

If you read the first page of this thread and look at the UOA comparison sheet #3 (or read what has been posted in this thread), it would be wise to stay far away from Royal Purple in any VQ engine.

I think what people are forgetting here is that this thread is not a magical way to know what is the best of the best oil, it only shows statistics and the best way to find out what oil is best for your car is to try a few different oils and run a UOA on each fill!

 

There aren't many Castrol Edge UOA's done if I remember correctly, and as the poster above mentioned, Royal Purple seems to be rather terrible.

Mobile 1 has been decent overall, with Castrol Syntec 0w-30 (European Formula) and Castrol GTX 5w-30 both being above average.

Says who?

 

BTW, Mobile 1 filters and and K&N filters are virtually identical quality... so you can't go wrong with either one. The larger sizes fit, so you may has well get those instead (Mobile 1, M-110 or K&N ,HP 1010).

 

idk i've always heard people say 10w30 during winter 5w30 during summer i've been running 10w30 year round with zero problems? 124k miles right now.

 

It doesn't really matter because once the oil heats up, they effectively have the same weight.

 

It's the other way around, but depends on your climate to even be a concern.

 

so 10w30 is fine year round in tx lowest its gotten is like -5 here and highest is 115. or would their be a better grade for a car with 120k?

 

The dfferences between 0w-30 and 10w-30 isn't really an issue in TX.

In my opinion, get Castrol GTX 10w-30 if you want to use a conventional oil, use castrol syntec 0w-30 european formula if you want a synthetic.

 

I used M1 0W-40 (which is Mobil 1's European formula) because I'm boosted and want a little extra protection from a higher viscosity (at the expense of a few horsepower).

I also live in TX and the winter weight is irrelevant but the M1 0W-40 has shown to provide better results than either of the M1 5W-30 or 10W-30. If I were to go back to a 30 weight oil I would probably use the GC 0W-30.

 

Fellas, Castrol has revamped their synthetics. Castrol Edge with SYNTEC and Castrol Edge with Ti. I looked at some of the specs of the of the oils and they seem to be a heavier oil (SYNTEC) than before. 0w-30 European Formula has minimal changes and seems to be as good as the old one.

 

mobil 1 10 30 is on clearence at target 4 quarts for 11.74

 

Here's another report. All samples are from an '03, GTX-5w-30, K&N HP-1010 filter, no track days, daily driver.

 

Are any of your GTX samples the new formulation (i.e., API-SN, ILSAC GF-5) of GTX? Just curious.

 

I have no idea. They're just off the shelf from walmart.

 

to OP: any info on the castrol GTX 5w-30 vs Pennzoil conventional 5w-30 which has ratings: API-SN, ILSAC GF-5 ?

 

pennzoil conventional 5w-30 has this rating. Im using it currently and the engine idles smoother..have been using GTX5-30w since new. After reading BITOG, i decided to try it. Its working good so far.

 

Just pulled this sample--Pennzoil Ultra 5w30--from my 03 G35.

Oil filter: Nissan 9E000
Air filter: Airaid SynthaFlow

I'm happy with the low silicon and insolubles, but not super impressed with the Ultra.

(Previous sample was oil supplied by my mechanic, so I'm not certain what it is--either Castrol Syntec 5w30 or Castrol SynBlend 5w30. Air and oil filters were generic, no-brand filters.)

 

I have been reading this thread for most of the afternoon. I also read all of the chapters over at BITOG, all of which are a very good read.
Anyway I've noticed that even though the BITOG site says all oils are TOO THICK at startup, most people on this board and that one, stick with 5W- or 10W- oils anyway. Why? It's totally contrary to the entire guide. Also he states and reiterates that going thinner, rather than thicker, is better especially on lower mileage engines. But I tend to see people switch to 0W-40 instead of 0W-30.
Just an observation and I'm bored and there is nobody home to talk to.