Going back in time?...........

[othon]

So I bought a 2004 Subaru WRX wagon, up till 12,000 miles I was using Castrol GTX 5W 30. Then switched to Mobil 1 Synthetic 10W 30, after the first due date to change the Mobil 1 I noticed that the boxer motor had burned some oil. So I picked up some Mobil 1 15W 50 and when it was time to change that oil, I noticed it had burnt through some of that as well.

I did some research on some Subaru forums and noticed people (okay a lot of people talking about this) saying that when they switched to synthetic that they noticed the car burning oil.
Now other people that are still using regular dino oil are not noticing this problem.

So I’m going back to Dino oil, Castrol 20W 50 (I live in a hot area and like to run up and down the mountains around my area in southern California.)

What I would like to know which I’ve been having problems finding a definitive answer is……

"When I switch back to normal oil after using synthetic, should I run normal oil in the car for a few miles then drain that and add in the normal oil I’m going to keep till the next scheduled time? Or dose it not matter, cause some motor builders have told me that it dose help to do this because of the two oil's make up."

Just wanted to know what other people know about this and what they think.
Or if my bottom became a chimney.

[ January 22, 2005, 08:43 PM: Message edited by: 59 Vetteman ]

 

[KW]

Just change it over and drive, there is no need to rinse the left over M1 out. The little M1 left behind won't hurt a thing.

GTX 10W30 might be a better choice of oil over the 20W50. I'm just guessing here but the 20W50 is pretty heavy.

 

[pscholte]

othon,

Just switch and drive...I would start out with 10W30 and then if that doesn't work go thicker...I would not immediately go to 20W50 in that engine. Where in SoCal are you? Do you ever drive that spectacular stretch between Lake Elsinore and Laguna Beach?

PS I don't think you would burn the Elixer of Turbo trustworthiness (AKA SLX...GC), but just in case that engine burns anything syn I'd hate for you to spend more money on stuff that won't work for you.

 

[Al]

There is no reason that the vehicle should burn Synthetic oil and not dino. I also think 50 wt. oil is too thick.

 

[othon]

quote:

---

Originally posted by pscholte:

othon,

Just switch and drive...I would start out with 10W30 and then if that doesn't work go thicker...I would not immediately go to 20W50 in that engine. Where in SoCal are you? Do you ever drive that spectacular stretch between Lake Elsinore and Laguna Beach?

PS I don't think you would burn the Elixer of Turbo trustworthiness (AKA SLX...GC), but just in case that engine burns anything syn I'd hate for you to spend more money on stuff that won't work for you.

---

yah I run Hwy 74 "Ortega Freeway" on sunday morning have some breakfast and then head down to laguna beach and then back up pacific coast highway.

 

[othon]

quote:

---

Originally posted by Al:
There is no reason that the vehicle should burn Synthetic oil and not dino. I also think 50 wt. oil is too thick.

---

The only reason im running 50 wt. is because of how hot it gets here in So Cal.

Also I have to drive my car 100 miles a day for work every now and then on the freeway.

 

[ekpolk]

I'm surprised the SLX-Meister (pscholte) failed to mention that he's using GC/SLX in an Audi twin turbo, certainly a high-stress application. The Subaru-M1 problems may relate to M1's relative thinness. It's around 10 cSt (darned near being a 20 wt) whereas GC is over 12 cSt (darned near being a 40 wt. If you can find the stuff, it might be worth a try. My car (G35) tends to encourage spirited driving, if you know what I mean, and I can't get it to consume a drop of GC. And it turns in A+ UOA in almost every engine in which its tried.

and welcome aboard.

 

[ToyotaNSaturn]

If you're headed back to dino, why not try a HDEO such as Delo 400 or Pennzoil LL?

Do group III "synths" burn-off like PAO-based synths (M1) do in this engine??