New oil, is this just placebo?

[Nick R]

Originally Posted By: sciphi
I swear I noticed a difference going from a 5w30 Quaker State Torque Power ($14 for 5 quarts on clearance at Wal-Mart, bought 3 jugs) to 10w30 Valvoline MaxLife. The car seems more sluggish, and needs more throttle to move. It's also idling smoother. Filters were the same Advance Auto Total Grip, so it's not the filter. Gas mileage has strangely seemed to go up, though.

If it feels different, or if somebody else notices, then it definitely was the oil. Otherwise, who knows?



Yup, for me both Maxlife runs felt sluggish and resulted in a very audible, very prominent tick.

 

[Nyquist]

I just changed the oil in my Malibu to some new Q Ultimate Durability 5w30 (Dexos 1 approved), and I'll swear my fuel economy went up to 33 mph on my Malibu with the LZ4. . .

. . . Or maybe it could have been the 10 mph tail wind on the interstate.

 

[CATERHAM]

Exactly.

Unless you're going from a 50wt to a 20wt it's impossible to accurately determine for yourself the 1 to 2 percent fuel advantage you might get between a single grade or other claim of an oil.

 

[Gary Allan]

The shorter the typical trip length, the more it will make itself apparent. I'd say with a decent commute it might be possible to see the fractional difference. On a cross country tour, I doubt it would show at all. Going 1-2 miles per cold start? Definitely.

 

[Whimsey]

Originally Posted By: Gary Allan
The shorter the typical trip length, the more it will make itself apparent. I'd say with a decent commute it might be possible to see the fractional difference. On a cross country tour, I doubt it would show at all. Going 1-2 miles per cold start? Definitely.


In my pre BITOG days I always thought that "thicker is better". In my then new 1996 2.0L Contour after the first year I went from Mobil 1 5w30 to Syntec 5W-50 and Quaker State Synthetic 5W-50 oil. Both caused my mpg to plunge on the highway, most of my driving, and the car felt sluggish. After 3 years I went back to Mobil 1 5w30, Exxon 5w30 Synthetic and then to Schaeffer's 7000 5w30. My mpg shot up and the car has a lot more pep. My 2.0L engine is definately a lot happier on 30 weight oil than 50 weight oil.

Whimsey