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.