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First oil change... Wow 5w/20 is like water

22K views 158 replies 47 participants last post by  cmaggi2 
#1 ·
Yea I know, another oil thread. :facepalm:

My Jeep is at about 700 miles and I wanted to switch over to synthetic. I have always used 10w/30 or 10w/40 Mobil 1 depending on the vehicle, and never had one that called for a 5w base oil.

The bulk of the factory oil came out of the pan in about five seconds. I'm actually wondering if this is a CAFE thing to squeak an extra 10th of a MPG out of the Pentastar rather than a protection thing.

No visible metal shavings in the pan or on the filter, so I'm going to go to a regular 4k oil change schedule but I'm considering going to 10w/30 if I hit that mileage by the hottest part of Summer.

PS: The JK is an absolute *breeze* to do an oil change on. Ironically, this is mainly due to lack of undercarriage protection. My 2 less off-road worthy pickups (Titan & Tacoma) both have factory metal skid plates protecting the oil pan that have to be removed. :whistling:
 
#3 ·
WOW, another synthetic oil user. The oil company's will love you!!!
I need to buy some more Mobil stocks so I can retire some day.
Thank you for helping my retirement..................

What ever oil you use, 5w/30 is a good multi viscosity.
 
#4 ·
My good friend is a millionair because of Mobil stock. He worked for them and part of his wage was paid in stock and about 15 years ago sold his stock and was instantly rich.
 
#8 ·
I use Pennzoil Platinum. Yes, 5w-20 is like water.

For those that hate on synthetic oil.. They're the same people that still watch over-the-air television and have land-line phones in their house. They probably read print media as well.

Newsflash: It's 2013.

Ignore them.
 
#17 ·
damn 8000 miles and my "change oil" indicator still has not triggered. 2013 jku.
 
#20 ·
I find it weird that the 2012 Pentastar uses 5-30w, and the 2013 uses 5-20w. I am using the 5-30w in my 2012, but I really don't like the light weight of the oil. I have always used 10-30w in the winter, and 10-40w in the summer. In North Carolina I used 20-50w in the summer. Although these Pentastar engine have a variable vane oil pump. It is electrically controlled, which make me think of all the problems later down the road. We are never going to get the miles from these engines that we got from the 4.0 liter. That is why I kept my old Jeep.
 
#21 ·
I have a 2013 Rubicon and after a lengthy conversation with my Dealers Service Manager, whom has a 2013 Sahara, we are both using 5w/30. The 5 viscosity gets the oil quicker at start up and the 30w at normal operating temperature will offer the needed oil film of protection. Please keep in mind that we are in Phoenix and we have already seen over 100 degrees this year.
Their Service Manager has been back to the plant this year and has not been able to get any justification as to why 2012 5w/30 and 2013 5w/20 recommendations. His take on it is for them to meet the Federal mandate on fuel consumption, they are using lighter oil for less parasitic loss.
It just doesn't make sense.

As to will the Pentastar run as long as the 4.0. Well very few engines if any do.
Only time will tell.
 
#22 ·
I have a 2013 Rubicon and after a lengthy conversation with my Dealers Service Manager, whom has a 2013 Sahara, we are both using 5w/30. The 5 viscosity gets the oil quicker at start up and the 30w at normal operating temperature will offer the needed oil film of protection. Please keep in mind that we are in Phoenix and we have already seen over 100 degrees this year.
Their Service Manager has been back to the plant this year and has not been able to get any justification as to why 2012 5w/30 and 2013 5w/20 recommendations. His take on it is for them to meet the Federal mandate on fuel consumption, they are using lighter oil for less parasitic loss.
It just doesn't make sense.

As to will the Pentastar run as long as the 4.0. Well very few engines if any do.
Only time will tell.
Doubt it. 4.0 was a beast. Hard to duplicate that.

It seems nobody agrees (including the experts) on the synthetic/conventional debate so I'll just do my own thing.
 
#29 ·
Motor oil is responsible for a large percentage of the cooling that takes place within your engine. Your radiator (anti-freeze system) is only responsible for cooling the upper portion of your engine. The rest (crankshaft, camshaft, timing gears, pistons, main and connecting rod bearings and many other critical engine components are cooled mainly by the motor oil within your engine.
Heat is generated within an engine from both the combustion process and the friction caused by the motion of engine components. As oil passes through the system it is directed onto these hot surfaces in order to carry the heat away to the oil pan. From here the heat is dissipated to the air surrounding the pan.

Read more: What Does Oil Do - The Motor Oil Evaluator
 
#34 ·
I bought a new 2002 F150 with the new triton engine and it was about the first engine that used 5-20 oil. It had very close tolerances in the rod bearings and they had issues early on with oil that was higer viscosity. Never used anything but motorcraft 5-20 and it is probably turning 400,000 miles by now.
 
#42 ·
Never try to convince the eternally retro automotive crowd that their grandfather's wisdom is incorrect. They are wedded to rope seals, iron engine blocks, distributors, distilled water in their four core brass radiators, drum brakes, greasing the steering box, 6 volt electrics, and single weight oils [20w in winter and 40w in summer].

They believe that their grandfathers taught their sons that automotive engineering ended with the 1948 Nash Business Coupe and what was good then, is wholly appropriate now.
 
#47 ·
I'm running 10w30 Mobil synthetic in my 3.8. And in my opinion it runs better. It may be a little thick for winter temps. But summer temps I think it's fine. Normally in auny other engine iv had. Iv alway run 10w30 in summer and 5w30 in winter. 5w20. Is just water.
 
#49 ·
If you think this oil is thin, my 2006 SRT-8 Magnum used 0w/30 Mobil 1. $100 oil changes!

I use what the owner's manual tells me to. I check my oil often and normally don't change it until the color darkens or the oil indicator says to. With new engines I have never changed before 5,000 miles of normal driving.

To keep my Warrranty on the Wrangler, I have had to change it at the 6 month interval with the low miles I have put on it.
 
#51 ·
Ask him what the TSB number is? I would like to verify the TSB which is simple if you have the number. thanks
 
#55 ·
he's a dog not a cat:whistling:
 
#59 ·
not that I have any faith in local dealer but they said they know of no tsb stating you can use 5-30 in place of 5-20. I would like to have the actual number so I could have them pull it up.
 
#64 ·
I haven't seen a TSB saying you can use 5w-30 in all of our engines. I do know there was some training that came out telling us that 2013 Pentastars use 5w-20 not 5w-30 and there was an oil filter change. They look the same but they aren't interchangeable. The oil filter might be the 2014 3.6, but I know it changed for one of those years.

But I know for a fact you can not put 5w-30 in all Chrysler engines. If you put 5w-30 in a 5.7lt Hemi MDS VVT engine you will get a CEL for P1521-INCORRECT ENGINE OIL TYPE. And you need to use the oil weight that your engine says. They are designed & engineered for a certain oil weight & variable valve timing engines use oil pressure to adjust that & if they have the wrong oil in them the oil pressure won't be right.
 
#65 ·
Thanks.
 
#66 ·
What's interesting to me is how often people confuse viscosity and lubricity. I don't wish to underplay the importance of an oil that maintains its integrity during high temperature operation - but, that is a function of far more than just viscosity. As noted (or alluded to) by a previous post, the chemical structure of the oil is a key player - how good is the base oil, what is the additive package like, etc. Ultimately, a higher quality 5-20W oil can be more resistant to thermal viscosity break down than a low quality 5-30W oil. Simply pouring a "heavier" oil into the engine does not, in itself, guarantee better protection.

It's worth noting that the engine's operating temperature is the big player here (in determining viscosity requirements). I see a lot of posts talking about matching oil to air temperature - which is a pointless and fool hardy exercise. If your engine oil is running at 250 degrees it doesn't matter if it's 100 degrees outside. Likewise, if it's running at 300 degrees it doesn't matter if it's 0 degrees outside. Ambient temperature matters for two reasons: viscosity on start-up and its effect on your engine's ability to cool itself.

Ultimately, what you want is the right viscosity for you engine (be it 20W or 60W) with minimal pumping issues at start up. However, there IS such a thing too much viscosity. Your engine's ability to circulate the oil properly, particularly at high RPM, is negatively affected by too high a viscosity. Less oil flow means higher stress on the oil that IS present and, quite possibly, less protection for your engine parts. Your engine is designed around a certain oil viscosity range at operating temperature - it's entirely possible that more than one oil weight falls into this range at operating temperature - in which case it's driver's choice.

As far as synthetic or petroleum based oils - synthetic are better. That's a matter of chemistry - you can debate that only from a position of ignorance. Now, just because they're better doesn't mean a thing - it's all a value judgment on the part of the operator. Everyone makes their own choice about what is best for their vehicle and what makes them feel "warm and fuzzy."
 
#72 ·
Well stated! :thumb:

As has been discussed the factory has serious conflicts of interest - e.g. the market pressure to increase EPA ratings, and the fact that post warranty they have explicit financial interest in the premature failure of your engine and your car. The fact that they are recommending the same viscosity for Alaska as Arizona is a little fishy to say the least. Blindly trusting corporate lackey engineers makes life easy but there's no real substitute for thinking now and then.
If you think about it, that's the primary reason multi viscosity oils exist: to work in cold or hot climates, Alaska or Arizona.
 
#69 ·
I generally trust what a tech says over a service writer. I have friends who are service writers and they are nice guys but mechanically they are not the same as a trained tech. They will tell you as much.
 
#77 ·
For giggles, figured I'd mention I saw a Mobil 1 commercial for "15,000 miles of guaranteed protection."

The gist of the commercial is a guy running a cab company grabbing up old Interceptor model Crown Vics at the end of their stint in public service and converting them to cabs - the implication being that Mobil 1 and 15,000 mile drain intervals will keep even a hard used car running for well into six figure mileage.
 
#79 ·
I cover all the bases. I'm running 5-30 and have a oil pan heater that I plug in during the winter but should do it year round. That way my oil is around 120 degrees when I start the engine. Since I have an oil pressure/temp gauge in my 3.6 it's easy for me to gain empirical data between cold starts and warm starts.

I believe it's most important using a pan heater during winter, but summer use is also beneficial. My engine starts very easily and warms up very quickly during winter when I use the pan heater. Low idle is reached very quickly. It's worth looking into if you care about such things...
 
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