Picked up some Subaru Synthetic 5w-30

[CATERHAM]

Originally Posted By: SubLGT
Originally Posted By: CATERHAM
..............BTW, Ford spec's a 5W-20 for the 4 cyl turbo in it's line up.

Subaru does not allow anything lighter than a 5W30 in their 4 cyl turbo motors, even though at 5000 rpm with a warmed up motor the oil pump relief valve gets a vigorous workout. Up until this year, they approved of viscosities up to 20W50, for severe use.

The problem is, if you're not seeing oil temp's any higher than 176F you're not getting the oil hot enough.
If your oil temp's were getting up closer to 100C the by-pass valve would of course remain closed.
Subaru doesn't recommend 20wt oil for it's turbo engines because higher oil temp's are expected. I'd look into why you're not seeing higher oils temp's. Being a part-time racer, my first instinct is to ask how much hotter the oil gets on the track, but I realize you don't race the car. Anyway that's something I'd enquire about.

 

[SubLGT]

Originally Posted By: CATERHAM
............The problem is, if you're not seeing oil temp's any higher than 176F you're not getting the oil hot enough...........


176 degF is not a normal operating temp in a turbo Subaru. I don't have an oil temp gauge, but those who do are reporting average oil temps on the street around 200-215 degF. Even at those average temps, reported oil pressures are in the 80-90 psi range at higher rpms. The relief valve begins to open at 85 psi. Reported pressures at cold idle (1500 rpm) on a cold start with 5W30 are typically 100-105 psi, with ambient temps of 40-50 degF, and I see that with my car also.

 

[furiouswrx]

I think dumping the FF at 1500 mi is a bit early; 3000-3750 mi is more appropriate. I changed mine out at 5135 mi and its viscosity at 100 C was 8.06 cSt, so that was a bit too long.

How cheap did you get that 5W-30 Subaru Synthetic oil? At my dealer it's about $6.75/qt with coupon and tax. I can get new 5W-30 Castrol Edge with Titanium FST or Syntec for about $5.98/qt with tax at Walmart..that's what I'm running now in my 2011 WRX.

 

[rationull]

Originally Posted By: furiouswrx

How cheap did you get that 5W-30 Subaru Synthetic oil? At my dealer it's about $6.75/qt with coupon and tax. I can get new 5W-30 Castrol Edge with Titanium FST or Syntec for about $5.98/qt with tax at Walmart..that's what I'm running now in my 2011 WRX.


It was $7.50 or so, which is about a buck cheaper than any synthetic not on sale at auto parts stores around here. I haven't checked Walmart -- I probably will but it's not in a convenient location for me generally. Obviously better deals can be had with sales too. But I was impressed that they weren't gouging for it.