5-20 wt VS 5-30 wt
The dealership did an oil change and used 5-20 wt Pennzoil synthetic with Mopar filter. The oil filler cap says 5-30 wt. I asked about this and was told that all the new 3.6 engines use the 5-20 wt. I was wondering if that was due to the recalls of the earlier head problems. Does anyone have any feedback on this?
I would go by what's shown on the oil cap as well as what's in the owners manual. My 2012 uses 5w-30 oil....Maybe he got the weight confused with the 3.8 engines or maybe the earlier 3.6 engines at one time used 5w-20 


¥



¥
God only knows what kind of oil the dealerships use. I wonder if they even change the filter all the time. You can only be sure the oil change is done right by doing it yourself. And it's so easy on a 2012 and 2013.
Most manufacturers are recommending 5w20 in all their newer vehicles for fuel efficiency reasons. They need to meet tough (and getting tougher) mpg standards, and every 0.25 mpg matters, from that perspective. Consider also that from their perspective your Jeep only needs to last until the warranty expires. I would use 5w30.
Also, I second what someone else said above - God knows what those dealerships are putting in your engine, probably the cheapest oil they can get away with. Wouldn't surprise me if they took the oil out of somebody else's pan and dumped it into yours (kidding, but not really...). I do my own oil changes - takes less time than driving to a shop and waiting, and I know it's done right and with good quality fluid. And the 3.6 is REALLY easy, with the drop-in filters on top (I don't have the 3.6 in my Jeep, but my Durango has the same engine - easiest oil changes I've ever done).
Also, I second what someone else said above - God knows what those dealerships are putting in your engine, probably the cheapest oil they can get away with. Wouldn't surprise me if they took the oil out of somebody else's pan and dumped it into yours (kidding, but not really...). I do my own oil changes - takes less time than driving to a shop and waiting, and I know it's done right and with good quality fluid. And the 3.6 is REALLY easy, with the drop-in filters on top (I don't have the 3.6 in my Jeep, but my Durango has the same engine - easiest oil changes I've ever done).
I often wonder this too? The 3.8 in my 2011 calls for 5w20 but I've often heard that 5w30 would protect my engine better, so which is better if I didnt care about the miniscule improvement in gas mileage that is completely negated by the mods I've done anyway? And why would it be better? Because I've always heard that thinner oils get up to operating temps faster because they dont get as thick when cold, thereby protecting the engine at the most vulnerable point...start up when the engine is cold.


