WHAT RIGHT OIL TO USE FOR JEEP WRANGLER 2011 3.8L

[Edbergh]

Greetings, I need some help with the following, the last time a local mechanic changed the oil of my "JEEP WRANGLER JK 2011 3.8L Gasoline" , he put in SAE 10W-30 synthetic brand by CAM2 Super Pro Max, API Service SN-RC ILSAC GF-5,
the Manual says to use API certified 5W-20 meeting Chrysler standard MS-6395, now the engine has already 91000 miles on lt and the average temperature where I live is around 31 - 32 degrees celcius ( 88 degrees faherenheit ) I need to have the Oil changed,
do I keep on using the SAE 10W-30 or go back to the 5W-20? please give me your expertise. thank you.

 

[BrocLuno]

With 91,000 there is enough accumulated wear that somewhat thicker oils are fine. No fear there.

It's just what you want and what sounds OK. If it's clicking and clacking on cold start with 5W-20, you know it's time to step up a grade ...

If it's still quiet and the oil pressure light stays off idling on the hottest days, you can continue to run 5W-20.

You are in the mileage zone where either can work fine ...

 

[CT8]

The 10w-30 is good to - 17c starting temps and the 30 part is fine

 

[IndyFan]

Originally Posted by Edbergh
Greetings, I need some help with the following, the last time a local mechanic changed the oil of my "JEEP WRANGLER JK 2011 3.8L Gasoline" , he put in SAE 10W-30 synthetic brand by CAM2 Super Pro Max, API Service SN-RC ILSAC GF-5,
the Manual says to use API certified 5W-20 meeting Chrysler standard MS-6395, now the engine has already 91000 miles on lt and the average temperature where I live is around 31 - 32 degrees celcius ( 88 degrees faherenheit ) I need to have the Oil changed,
do I keep on using the SAE 10W-30 or go back to the 5W-20? please give me your expertise. thank you.


I've got 127k miles on my 08 3.8 JK and I've run everything from the recommended 5w20 to 0w40, and everything in between. It runs the same on all of them. I was chasing oil usage and the only oil that made a big difference was Mobil 1 High Mileage, and it didn't matter if it was 5w20, 5w30, or 10w30. It reduced the oil consumption by about 25%. (The 0w40 did ok, but not quite as well as M1HM) It has always run, felt, and sounded like new, so the consumption was just a minor headache. It started at 40k and stopped or slowed dramatically at 116k after changing an upper oil pan gasket. (Funny, though, I never saw even a sign of seepage on that gasket.) Right now I'm running Pennzoil Platinum 5w20. It sounds/feels great.

I've never heard unusual noise or had an oil pressure light go on. If it did come on, instead of running heavier oil, I'd take it right to my dealer. (I have a lifetime warranty). That would not be a normal healthy engine and would, in my humble opinion, have nothing to do with the 5w20. I do agree with BrocLuno, though, on going to 5w30 if you hear noise or perceive noise. It certainly won't hurt anything with that engine. It should last a long, long time just following the maintenance schedule. Btw, change those spark plugs at 50k, and go with OEM Champion plugs. The 3.8 likes those plugs MUCH better than Bosch or NGK, both of which I've tried. The gap starts to widen up a bit at 50k. If they look good, just regap and reuse, but they will look like crap by 100k.

 

[Edbergh]

Hi Brocluno,

I want the engine to run smooth and not to cause unessesary wear because of different oil placed in instead of what the manual prescribes, there is no clicking nor clacking on cold start with the 10w-30 already in it, no oil pressure light coming on while idling with temperatures of arrounf 88 to 90 degrees OAT here, however I had to replace the fan motor and radiator about 2 weeks ago
and temp rose to 3/4 but since replacement of the fan motor and radiator its steady in the middle I also am checking with an
OBD II ELM 327 and the engine coolant tempt kickes in the fan motor at exactly 102 degrees celcius ( 215.6 deg. farenheit)
is this the right tempt. for the Fan Motor to kick-in. ?
Can I keep on using the synthetic oil or do I need to use mineral oil instead?
Finally, what is the best engine coolant liquid to use for this 2011 jeep considering the high temp. where I live.
many thanks in advance regards, ed..

 

[IndyFan]

Originally Posted by Edbergh
Hi Brocluno,

I want the engine to run smooth and not to cause unessesary wear because of different oil placed in instead of what the manual prescribes, there is no clicking nor clacking on cold start with the 10w-30 already in it, no oil pressure light coming on while idling with temperatures of arrounf 88 to 90 degrees OAT here, however I had to replace the fan motor and radiator about 2 weeks ago
and temp rose to 3/4 but since replacement of the fan motor and radiator its steady in the middle I also am checking with an
OBD II ELM 327 and the engine coolant tempt kickes in the fan motor at exactly 102 degrees celcius ( 215.6 deg. farenheit)
is this the right tempt. for the Fan Motor to kick-in. ?
Can I keep on using the synthetic oil or do I need to use mineral oil instead?
Finally, what is the best engine coolant liquid to use for this 2011 jeep considering the high temp. where I live.
many thanks in advance regards, ed..


I run nothing but synthetic. That engine is known for having hot spots and some theorize that those are responsible for oil consumption. I'm not sure about all that, but it has always run perfectly on synthetic. As for coolant, probably the reason the radiator had to be changed was due to using over the counter coolant instead of the prescribed Mopar HOAT. I've had mine flushed/filled twice, at each 50k miles or 5 years, by the dealer with the proper Mopar HOAT (Hybrid Organic Acid Technology) coolant and have had zero issues with the cooling system and no gunk buildup. I'd stick with that, at a 50/50 mix with distilled water or pre-mixed. Zerex g-05 is the same stuff, just a different color, and I'm pretty sure they make the Mopar HOAT. If you ever have to put anything else in there, then flush it out first chance you get and replace with HOAT. Every single 3.8 Jeep owner I know had cooling system issues by 100k if they ran anything other than HOAT, ranging from clogged heater cores to replacement of the radiator. I don't know the technical reasons, but I know what works. That temp sounds about right. My JL kicks up the fan at a higher temp than that, so I think you are probably good there.

This engine should last 250,000 plus miles if treated right. I took mine to Moab in 2015 at 90k miles and ran the [censored] out of it in high heat with the air conditioning running 1/2 the time and it had no issues. I was running M1 0w40 on that trip, but I think it would have been fine on 5w20, too.

I would highly recommend a new set of Champion spark plugs, too, and maybe wires at 90k. Be sure to gap them correctly. That alone can make a big difference in how it runs.

Is your 3.8 using any oil? If so, don't be alarmed because sometimes that's a simple fix, and if not, these things just keep running anyway. I haven't seen a 2011 with that issue yet, so I'm guessing not.

 

[IndyFan]

One more thing...Don't worry about unecessary wear with 10w30. It is fine if you want to keep it in there. The 5w20 won't cause unusual wear, either, though. Run the oil weight in which you have the most confidence. That engine will be fine either way, or with 5w30. I've run it all, in the hottest conditions and in below zero conditions. It started/ran/sounded/felt the same, to me.

 

[Edbergh]

Hi IndyFan,

Thanks for all the valuable info I see you know your stuff, the engine does not consume oil sofar as I know and no leakage spotted
below or on the block itself, one thing your right on the nail is the coolant, I used a over the counter allready mix brand called
"RED-COOL" Anti Rust radiator additive made by HERRERO & SONS CORP, from Miami, Fla. ( www.herreroandsons.com )
since they don't sell any Mopar HOAT on the island.

 

[OVERKILL]

Originally Posted by CT8
The 10w-30 is good to - 17c starting temps and the 30 part is fine


?

10w-30 is good down to -25C as per the CCS temp. It has to pump at -30C (MRV).

 

[CT8]

Originally Posted by OVERKILL
Originally Posted by CT8
The 10w-30 is good to - 17c starting temps and the 30 part is fine


?

10w-30 is good down to -25C as per the CCS temp. It has to pump at -30C (MRV).
Better yet the viscosity chart I have puts the 10w at 0*f.

 

[Edbergh]

HI CT8,

The average tempt. here on the island is around 32 degrees celcius ) ( 90 degrees farenheit )

 

[OVERKILL]

Originally Posted by CT8
Originally Posted by OVERKILL
Originally Posted by CT8
The 10w-30 is good to - 17c starting temps and the 30 part is fine


?

10w-30 is good down to -25C as per the CCS temp. It has to pump at -30C (MRV).
Better yet the viscosity chart I have puts the 10w at 0*f.


J300 is in Celsius though

 

[ka9mnx]

Sounds like you have a very good/smart mechanic...

 

[JLTD]

10w-30 in your climate is a very good choice. The original specification for the 3.8 was a 30 grade oil.

 

[demarpaint]

10W30 is fine for your climate. Oil use is something a lot of 3.8L Wrangler owners complained about. IIRC there were many assembled with the piston rings installed incorrectly which was the root cause of the problem in those engines. There is a lot of info on the web about it. You could try a PCV valve replacement, get an OE part.

 

[dave1251]

Originally Posted by Edbergh
HI CT8,

The average tempt. here on the island is around 32 degrees celcius ) ( 90 degrees farenheit )



You could use a 20W50 and not worry about it being too thick for a cold start.