For the EJ20T and others:


There is a lot of mixed info on using Synthetic oil on Turbocharged cars, untill they reach "HIGH" miles.

IMO, I am going to use Castrol GTX.


Just thought I would see what people are unsing and believe in.

 

I personally use Mobil1 synthetic (5w30) in my car. From my own previous experience, I find that the synthetic helped in the area of oil temperature and heat dissipation. The synthetic oil cooled quicker than the natural oils in my previous cars after some hard runs (atleast that's what the oil temperature gauge indicated).

 

I switched to Castrol GTX at 10,000 miles, and I could literally feel the difference on the drive home -- I have no idea why, but the engine seems to idle a bit lower and rev a tiny bit quicker. The syn oil also seems to come out a bit cleaner during changes.

I did however wait to switch, as my dealer shop mechanic reccommended. He said that certain engine gaskets and seals are designed to operate with high-pressure oil literally being forced into their pores and microscopic cracks, and the dino oil (also being made of petroleum) does a better job "impregnating" (his word, not mine!) the seals with oil.

In a related note, we have a Legacy Wagon (2.5l) and I just had to replace the cam gasket and some other minor gaskets at only 36,000 miles on the engine. Why? It was my grandfather's for 18k of those miles, and he drove it perhaps three tims a week, probably less than three hours total. By NOT driving it, according to the shop where I had it fixed, the gaskets were allowed to "dry out" and didn't get the oil saturation that they needed, and thus developed larger cracks and finally splits. A cautionary tale!

 

I switch to synth after 10K of dino oil.

 

Might do the same




:banana:

 

The dino oil I always use prior to the synth is Castrol GTX 5W-30. I've always used mobil 1 when I switch, but in my F-XT which just turned 10K the other week, I used Royal Purple. There is a local speed shop that carries it and it costs the same as Mobil 1 so I thought I'd give it a try.

I change the oil at 1K the first time then every 3K miles after that. So the 5th time I go to Synth. I've always done that with my new cars and have never had a problem. I know people change to synth sooner and there seems to be a lot of debate about when.

 

after 10k miles i only use mobil one syn

 

wha's "high"?

 

80k or so....

 

I used dino oil for the first 3,000 miles, and then switched over to Mobil 1. I used mobil for the next 10,000 and then, after reading up, I switched over to AMSOIL. It is a little more expensive than Mobil 1, but it "seems" to run better. This is being guaged totally from my butt dyno which has been highly indoctrinated from my brain dyno, but take it for what it's worth.

As for changing so early (3k instead of 10k) I think next time I will wait until 6,000 to change over to synth. The more I read, the more I wish I had waited, but so far (knock on wood) I have not had ANY engine trouble on my '02 WRX Wagon.

 

let's see if i got this right, you're going to use dino oil till about 80k miles, then switch to syn?

if so, then that doesn't make any sense at all.......i've seen tons of arguements about having to wait, but usually only till 10k miles. the purpose to waiting to so that the engine can properly "seat" itself

but waiting that long? you might as well stick with dino all the way then......it might actually be more detrimental to the motor if you wait that long. build up in the engine could be dislodge when you switch to syn at those high milage.

in any case, if you properly change the oil at a set interval, your motor should last

btw, where did the idea of switching to syn at that high a milage came from?

 

I have heard from people in the past with turbocharged hondas that Synthetic is not necessary on low milage turbo cars. Castrol GTX is a very good oil. Things tend to "loosen" up on higher milage cars. Wrist pins, rings ect.

My engine builder of my old Honda told me to run the GTX. I no issues with it. I am not sure what the EJ20T likes better. That's why I ask.

 

I use Castol Synthetic.

 

I run Mobil 1 5w30 in cold season and 10w40 in the summer.

From tje research I have done, synthetic oil will provide much higher protection under ALL conditions, especially cold start and at high temperatures. Most petroleum-based non-synth oils break down rapidly over 266F, not sure if the WRX gets to that level, but I am more confident using an oil that has a higher threshold and does not oxidize as rapidly as a non-synth oil. For more info read the books "Four Stroke Performance Tuning" and "Forced Induction Performance Tuning" both by A.G. Bell, available from Haynes Publishing.

 

after break in use synthetic cuz it does not break down as easy and can withstand the high temps of turbo engines...

my 2 c