quote:
Originally posted by Ed_T:
I'd use it as a top-off or in small ratio in warm weather only. I just topped my LGT with 1/2 qt. M1 15w-50 and 1/2 qt. M1 10w-30, and from what I can tell that little bit of 50 added some stiffness, which the 2.5L seems to like (Rotella synth in the pan to start with).
Once it gets flowing it'd be hard to beat, esp. in the Subie engine. I've found the higher weights seem to cause this engine to pull harder after hitting spoolup with a noiseless effortlessness (except for that great exhaust note) than with the thinner factory recommended weights.
BTW I get slightly quicker spoolup with RTS than with TSUV 5w-40 (which lamentably is "gone"). I'd expect some slight lag with the RL. If you have a catless uppipe this probably wouldn't be an issue, if it even is one.