2012 Jeep Grand Cherokee-Pentastar 3.6L V6

[GAT72991]

Hey guys,
Long time lurker, first time poster. I did search the forums and can't quite find the answer I'm looking for. I just bought a 2012 Jeep Grand Cherokee with the Pentastar 3.6L V6. The owners manual calls for 5W-20 Full Synthetic, but there is a supplement with the manual that calls for 0W-40 Full Synthetic. What oil is recommended for this engine? Does anyone know why Jeep changed this, was it to meet CAFE standards or something else? I don't know all the ins and outs of this engine, but I just don't feel comfortable putting a 0W-40 oil in this engine, whether it be overhead roller-follower valve train or not. I understand that too thick an oil is unnecessary in these new engines due to tighter tolerances and different design, and that too thick an oil could impede proper VVT operation. I also plan to stick with an OEM Mopar filter. Does anyone have any advice or experience first hand with this engine? What oil should I use for proper protection? Looking forward to the discussion.

 

[Volv04Life]

The 0w-40 spec is for the 6.4 SRT8 if im not mistaken. 5w-20 is whats on the oil cap of the newest 3.6 engines. Id use Pennzoil conventional 5w-20 and be happy.

 

[GAT72991]

Volv04Life,

Thanks for the feedback. Looking forward to any more opinions. I've heard good things lately about Pennzoil but I've always used Mobil1. Anything certain you feel is a strength of Pennzoil over anything else?
Mods,

I just realized I posted this in the diesel engine forum, my apologies. If someone could move it appropriately It would be appreciated.

 

[demarpaint]

When the Pentastar was first used in the Wrangler in 2012 it called for 5W30. From 2013 on they started spec'ing 5W20. I thought the GC with the 3.6 used 5W30 as well in 2012. I learned something new today.

 

[KCJeep]

Since you are in SC I would just run the original spec, a good 5w30.

 

[Hokiefyd]

GAT, welcome to the forum!

The supplement recommending 0W-40 is likely for the SRT version of the Grand Cherokee. 5W-20 is the correct specification for your Pentastar, and I don't see you gaining anything from using something that's heavier than necessary. Your engine uses a variable displacement oil pump that will vary the flow to achieve the pressure it wants anyway. Use any 5W-20 of your choice and enjoy that nice engine.

 

[The_Captain]

As an owner of a 2012 Grand Cherokee I can assure you that the 2012 calls for 5W-30. The switch to 5W-20 did not take place till 2013. So, if the OP does in fact have a 2012 then 5W-30 is the correct oil!

 

[demarpaint]

Originally Posted By: The_Captain
As an owner of a 2012 Grand Cherokee I can assure you that the 2012 calls for 5W-30. The switch to 5W-20 did not take place till 2013. So, if the OP does in fact have a 2012 then 5W-30 is the correct oil!


That's what I though, I guess I didn't learn something new the other day.

 

[GAT72991]

Thanks for all the welcomes and replies so far guys. So I've definitely gathered that the 0W-20 spec supplement is for the SRT model. However, I'm still unsure whether to go with a -20 or a -30. Also, I've read that Mobil1 Full Synthetic does not meet Chrysler's minimum spec; does this hold any logic? I've always used Mobil1 and never had any problems. I've ran it in two of my previous Mustang engines (4.6L 2V and a 3V) and never had any issues or abnormal wear through Blackstone's oil analysis. I use it in a 2001 Grand Cherokee 4.0L that currently has 205K and doesn't make a sound, runs like a sewing machine. I just don't understand why it wouldn't be suitable for this little V6. Also, does anyone have any opinions on Royal Purple and what weight to use if I went with it? Not sure what the dealer fill was but I'll be sending it off to Blackstone as soon as I drain it.

 

[Clevy]

Originally Posted By: GAT72991
Thanks for all the welcomes and replies so far guys. So I've definitely gathered that the 0W-20 spec supplement is for the SRT model. However, I'm still unsure whether to go with a -20 or a -30. Also, I've read that Mobil1 Full Synthetic does not meet Chrysler's minimum spec; does this hold any logic? I've always used Mobil1 and never had any problems. I've ran it in two of my previous Mustang engines (4.6L 2V and a 3V) and never had any issues or abnormal wear through Blackstone's oil analysis. I use it in a 2001 Grand Cherokee 4.0L that currently has 205K and doesn't make a sound, runs like a sewing machine. I just don't understand why it wouldn't be suitable for this little V6. Also, does anyone have any opinions on Royal Purple and what weight to use if I went with it? Not sure what the dealer fill was but I'll be sending it off to Blackstone as soon as I drain it.



Mobil 1 will easily meet any Chrysler spec however they refuse to get certified,and that's a whole other thread topic.
If you like mobil then use it.
As far as thicker oils affecting the vvt lets consider how thick a 20 grade oil is at -20c. Now let's consider that same 40 grade at operating temp
Which is thicker? Obviously the frozen 20 grade yet the vvt system seems to work in that situation,so why wouldn't it work using a 40 grade that's at operating temp?
I've got mds on my hemi and it operates just fine using a 40 grade in the summer. Fuel economy is unaffected.
So while under warranty use what they tell you however the old wives tales about hydraulic systems not working properly with oil that's slightly thicker should be left to the wives telling them.
When considering grade of oil consider the usage of the engine. Will you get it hotter than what's considered normal for any length of time?
Will it be towing anything,or short tripped a lot.
These are questions that will affect the choice of grade being used.
And no one ever had an engine fry from oil that was a grade or 2 thicker however I can think of guys whose oil was thin and shortly after a righteous night shredding tires an oil consumtion issue presented itself.
That being said if the engine will be "lady driven" then no need to go a grade thicker,just keep an eye on oil level.