B@lliZtiK:
" I just have my doubts about the effectiveness and useflulness of thicker oil like that in a car that probably won't see much high performance use. Simply to prop up a lifter tick problem, I don't think it's a good idea. Best to fix whatever causes that in the first place, IMO."
In general, I agree with you. High performance guys are often a bit too quick to go with a thick oil ... sometimes waaaayy too thick.
Many serious car people have figured out that thinner oils provide less drag on the motor and free up more horsepower. And if you load up the oil with additives like moly, boron and ZDDP, you can get protection which is just as good ... sometimes even better.
I've seen too many really good used oil reports from people using 5W-20 and even 0W-20 (and these had all thinned some!!
) to discount this method of engine protection.
This is the theory behind Mobil 1's racing 0W-30.
http://www.mobil1.com/products/racing_formula.jsp
But, for guys wanting a thicker oil, the 15W-40 fleet oils make a good choice ... better than the "racing" 20W-50s from Valvoline and others ... and waaayyy better than the straight 40 or 50 weight oils.
I also think the extra detergents in the fleet oils will (safely) help 'de-sludgify' an older motor which has been neglected. Trying one for a couple thousand miles is easier than tearing down a motor just because a lifter is sticking a little. That often happens because of sludge build-up in a critical area. gooey build up can restrict oil flow in certain places.
Then again, sometimes ANY oil change will free-up a sticky lifter because the additive package (including detergents) is that much fresher and better able to clean and lubricate.
