WestsydeGuy

I always use 5w30 in my cars and pickups that are gas.
Year round in every single one of them.
Now switched to bulk in barrels but still Mobil 1 5w30.
Either factory or napa gold filters on every one of them from my dodge trucks and hellcat to the F150s and Mustang.

Eric Kleven

Heads are clean, but that's not a melted piston: That's over-heating the ring pack with a stock ring gap. Rings got hot, ends butted, and then pushed up and down into the next ring pack. check this vid:
Pull an engine apart, open the rings appropriately for that much boost, and you could run that boost alll day long (or until the rods got crushed).


/hijack

mpd13078

Newport

I run 5-30 Mobil Super Synthetic in my 5.0 and 3.5NA. It works just fine but do stick to the FL-500 silicone valve filter. I did notice a slight MPG decrease in both vehicles when I switched over but not enough to worry about. I like the Super Syn because its specs almost match the Mobil 1 specs, are better in some instances and it is one of the less expensive synthetics on the market. The last cases I purchased I got for $3.25 / quart. I sucked up about 8 or 9 cases. The primary reason they spec a 5-20 is that is the oil they needed to use to hit the CAFE standard they chose. Never bump up the bottom number because you may create a lifter rattle. Hydraulic lifter tolerances decreased significantly when hydraulic roller and overhead cams showed up and running something heavier than a 5 sometimes restricts the oil flow enough that the lifter never bleeds off all of the air and then they rattle a bit.

Johnny Paycheck

That depends on external conditions. The cap on my 4.2 says 5w-20, but I’ve never run anything beside 10w-30 or 10w-40 and no engine damage of note from the lifters. Rattle is due to poor quality and machining. On a side note, I have a Hemi equipped Ram and by far 5w-30 is much better at keeping the lifters from eating the cam than 5w-20 is. But, don’t expect FCA to tell you that 5w-30 is better when CAFE matters more to them.

Truckin18

Pennzoil Ultra Platinum 5w-30 for me. With all the info listed on BTOG website and other performance manufactures recommending a thicker oil I don't see it harming anything. Just my 2 cents.
Truckin

Sharkhunt

5w-50 in a daily driven, left idling, sustained (top end of) highway-speed, towing, supercharged truck. 50wt is probably overkill if you don’t spin it way up there, just saying thicker oil is juusf fine.

Thisisme2

Years ago I read a report on oil use studies: I will try to summarize here:

The study was from a service / maintenance shop over very long period of time measuring many engines of many sizes.
All the vehicles were emergency types (plows, fire trucks, ambulances etc.... in northern Canada where it is not always possible to allow an engine to warm up in extreme cold conditions (extra time could me lives lost).

At the end of the study / report the only oil they would put in any engine was a 0w.

Lower rates of failure, lower cost and more dependability.

If I can find that study tomorrow I will post the whole thing.

Maybe others here have read about it?