0W-40 oil

[TheJerseydude]

Is there anything wrong with using 0W-30 fully synthetic oil on a 94 Q with about 200,xxx miles on it? I usually use 10W-30 but I mistakenly bought the wrong oil this time and decided to use it after reading the back of the carton. Just need to know if Im taking a big risk here

[jltibbs]

I would be liable to say that it may not be the right thing to do. I have no explanation (because I'm not a mechanic, nor an oil specialist), but I do know the car calls for 10w-30. I stick to what the manufacturer calls for in all 3 of my vehicles. I use conventional Castrol GTX and a premium filter; changed every three months regardless.

[maxnix]

0W-40 M1 is an ideal oil.

[qship96]

I am currently using Redline 0w-30 in my 240,000 mile old Q, 0w-XX is always a better choice then a 5w-XX or 10w-xx if you are using a synthetic oil- it protects better at startup, especially in winter temperatures.

I agree with Maxnix regarding mobil 1, their 0w-40 is their best oil, and one of the very best choices in "over the counter" easy to find oils.

[szh]

0W-40 M1 is an ideal oil.

Agreed. I used Mobil 1 Synthetic 0W-40 regularly in my 1995 Q45 for many years and now for the last six years in my 2003 M45 ... without any problems whatsoever.

Z

[3Q Jay]

did you buy 0w30 or 0w40? your post has one in the title and the other in the body.M1 0w40 is good stuff as others said. note that it has acea a3 rating, not just a1 rating. the only m1 ow30 i am aware of is the 'afe' version. it does not have the a3 rating.

i do like the gc 0w30 (both the green and gold variants are a3 rated, and have worked well in my g50s).

[Ace2cool]

I think this needs to be copied and pasted, with original author's permission, of course, into a general sticky. I keep coming across motor oil questions, and this answers all of them, plus many, many more that you would never even think of...

The best write up on motor oil that I've ever read in my entire life

[maxnix]

I think this needs to be copied and pasted, with original author's permission, of course, into a general sticky.

Actually, there are many previous eloquent posts on motor oil, unfortunately most got tossed into General Chat when the Q45 Forum was deemed not worthy of their transference. Good luck finding them.

http://www.bobistheoilguy.com is a definitive forum.

[qship96]

Easssssssssssssssyyy cowboy!!!

[TheJerseydude]

Wow I missed out a on all of the convo because I was moving home from school and didnt have internet access for a couple days so sorry guys but thanks a lot for all of the feedback. A friend of mine had me pretty worried about using the 0-w40 oil. And yes its mobil fully synthetic. From all of the comments it seems as if that is better to use than the 10-w30 I was using before. Also, I have no problem with someone "stickying" this page although I dont know how to. If I need to do it just leave the steps on a post and Ill do it within the next 24 hrs.

[mcrews]

I think this needs to be copied and pasted, with original author's permission, of course, into a general sticky. I keep coming across motor oil questions, and this answers all of them, plus many, many more that you would never even think of...

The best write up on motor oil that I've ever read in my entire life

What a great write up!!!! thanks for the link

I love how the Dr. segways here: "...It seems then that we should all be using the thinnest oil money can buy. This is partly true. Let me use my 575 Ferrari Maranello as an example. "

Yeah, let's use your 'piece of crap' car!!!! What...... the 250 California Sepcial got banged up in the Ferris Buelier Movie!!!! Well.....then what about the Testarosa .....it's just sitting there!!

[qship96]

?

[AdamLowther]

I use 0-30 synthetic every winter all winter. Its -33C here right now. Dino oil would be glue starting at that temp.

Not sure the manufacturer had winter in Canada in mind when they reccomended 10-30. Use some judgement, and things will be fine.

[loystock]

This thread got me interested so here's my 10 cents.

In fairness to the other guy (doctor), he was talking to fellow FERRARI car owners and NOT bragging to NICO members.

As for the 0W-40 oil, here’s my personal opinion. The Mobil 1 0W-40 Synthetic oil may be one of the best oil and meets the European (MB, BMW, etc) car lube requirements. But I have Japanese cars which have different specifications and whose reliability are way better than European cars. Per Infiniti FSM, I must be using 5W-30 (or 10W-30 at temp above 0F). The API grade is SG/SH for the older cars and SJ/SL for the newer cars. The 30 weight applies to all Infiniti cars that I have. The VK engine (03Q) may also use 5W-40 oil.

I switched to synthetic oil in the late 90s and only use 30 weight oil, typically 10W-30 and occasionally 0W-30 but never 20/40/50 weight. Per SAE J300 requirements, oil viscosities at 100C/212F (typical engine operating temperature) for the following weights are: 20=5.6-9.2CentiStokes (cSt); 30=9.3-12.4; 40=12.5-16.2; 50=16.3-21.8; 60=21.9-26.1.

So for my cars, the recommended viscosity at operating temp is @ 10cSt with 30 weight and not @ 14cSt for the 40 weight. If I use 40 weight, the oil is thicker than recommended and my oil pump load will be higher. Based on viscosity alone, I have optimum lubrication using 30 weight oil. Of course there are other API/ASTM/SAE parameters to be considered but viscosity is a common parameter published by oil manufacturers for comparison.

Since I only use Mobil 1 synthetic oil and AMSOIL is supposedly the best one (@ $4 more expensive than Mobil 1 Syn per quart), below are their published oil viscosities at 100C/212F and 40C/104F.Mobil 1 0W-30: 11cSt at 212F/63.1cSt at 104FMobil 1 5W-30: 11.3/64.8Mobil 1 10W-30: 10/62Mobil 1 ESP (Extended Service Performance) 5W-30: 12.1/72.8Mobil 1 HM (High Mileage) 5W-30: 11.48/68.5Mobil 1 HM 10W-30: 11.79/78.2AMSOIL 0W-30: 10.3/56.56Mobil 1 0W-40: 14/78.3Mobil 1 ESP 5W-40: 13.35/81.1Mobil 1 HM 10W-40: 14.71/98.16AMSOIL 5W-40: 13.7/79.7AMSOIL 10W-40: 14.6/90.5

Based on the above and what I know about oils, I have no reason to use 40 weight oil in my Infinitis. Maybe, if I have higher than normal oil consumption, I’ll go to higher weight. But I never have had that experience (knock on wood). I’ve been driving in the US for 27 years and I have never been stranded on the road (kow), never involved in an accident (kow) though I have contributed greatly to the CA state coffers (speeding tickets). All of my cars lasted beyond 10 years (except for the 04 G35 which was totaled when my daughter had a rear tire blowout) were in good condition and had original engines and transmissions when sold or given away. Having worked in the airline and semiconductor industry for a long time, preventive maintenance is the key in prolonging equipment/car life span.

[qship96]

Except ONE thing...all the above numbers represent brand new UNUSED oil, once put into use, the numbers change, and in particular the Mobil One oils.....the Mobil One 0w-40 has shown to quickly shear to a 30 weight oil which is what Infiniti generally specs! Beyond that, their 0w-40 is a much superior oil over their 5w-30 and 10w-30{ it is a true PAO synthetic basestock, whereas the others are not, they contain lots of group 3 hydrocracked processed mineral oil.Any of them will allow long engine life if changed regularly......but if you are paying for "synthetic", you might as well get the real thing!

[loystock]

Great! This is a valid reason to switch to real synthetic. I know 0W-40 is a true synthetic (Group IV) while the 30 weights are more like synthetic blend (derived from Group III).

I've been to other European and Japanese car forums, 'independent' oil lab companies and "bobistheoilguy.com." The consensus seems to be that Mobil 1 Groups III and IV oils viscosities are stable. There are threads about 0W-40 viscosity going down but there are no UOA (Used Oil Analysis) quoted. I could have missed something. In one site, a UOA of a 0W-40 after 12K miles, the viscosity @ 40C went up to 82cSt (new is 78cSt but no data available at 100C). This is more like AMSOIL where viscosity increases over time/mileage.

Has anyone done or has a record of VOA (Virgin Oil Analysis) and UOA on a Mobil 1 0W-40, and at what OCI?

[PalmerWMD]

Is there anything wrong with using 0W-30 fully synthetic oil on a 94 Q with about 200,xxx miles on it? I usually use 10W-30 but I mistakenly bought the wrong oil this time and decided to use it after reading the back of the carton. Just need to know if Im taking a big risk here

No risk involved of any kind to use this oil.Not a bad oil for the winter even tho I prefer the 0w-40 yeararound for a VH45de.

Dont havae time to discuss in more detail but this is your basic answer.If your engine burns oil you may see an increased loss but only by a small amount.

Again use the oil you have paid for its fine

[TheJerseydude]

Thanks everyone for their input especially PalmerWMD for getting straight to the point lol. I probably would have wasted 60bucks trying to replace the oil if it wasnt for you all

[PalmerWMD]

1)But I have Japanese cars which have different specifications and whose reliability are way better than European cars.

2)Per Infiniti FSM, I must be using 5W-30 (or 10W-30 at temp above 0F). The API grade is SG/SH for the older cars and SJ/SL for the newer cars.

3)So for my cars, the recommended viscosity at operating temp is @ 10cSt with 30 weight and not @ 14cSt for the 40 weight. If I use 40 weight, the oil is thicker than recommended and my oil pump load will be higher. Based on viscosity alone, I have optimum lubrication using 30 weight oil. Based on the above and what I know about oils, I have no reason to use 40 weight oil in my Infinitis.

I see you did your home work thats good I have a little more time right now to typeso here is my humble input:

1) Internal combustion engines are internal combusion engines no matter who makes them. then only thing that really affects your choice of viscosity is bearing clearances of which there are little differnces nowadays between the 2.

2) The Infiniti literature actuare also allows the use of 10w-40 in summer. For some of the newer cars it may not ( i havent checked) but keep in mind that beaing clearances on the VK45de are not tighter than on the VH45de (if anyhting they might be looser). Also the VH45de has very tight rings, tighter than the VK45de yet still allowed 10w-40 in summer.

3) It makes sense for you to aim for oil choice based on operating viscosity for your cars, which is basic physical chemistry.

But here is the kicker:Ambient temps during a USA summer are MUCH higher than in a european or japanese summer ( Especially in US south but even in the north you see 90 and even 100 F regularily which you dont in Europe or Japan except by rare exception). This mean oil temps will be higher. This will thin out your oil a bit,... enough IMO to make 40 weight oils the better choice in USA summers for VH45de and VK45de powered cars.

Fred...

PS: the SAE has viscosity dinwos ( as posted earlier) to what constitues a given viscosity in steps 30, 40 etc but for clarity's sake lets assume they published it not in classes but in greater granularity:

So its true the 0w-40 (which is really more like a 0w-38) tends to shear down after 2000-4000 miles a bit to somethng more like a 0w-34.But thats still better IMO than the xw-30 formulations from MOBIL which tend to run more like a xw-28., if there was such a thing.On the other end of the spec is the 0w-30 Syntec which starts out as a 0w-34 or so and tends to stay there for quite afew miles.
Modified by PalmerWMD at 11:52 AM 12/13/2009

[PalmerWMD]

Thanks everyone for their input especially PalmerWMD for getting straight to the point lol. I probably would have wasted 60bucks trying to replace the oil if it wasnt for you all

Good I am glad you will keep it.Its a fine oil for a Jersey winter

[loystock]

Thanks, Fred.

As I have said before, Mobil 1 0W-40 is one of the best oil in the market and AMSOIL is probably the best in the 30 grade. However, I stick with Mobil xW-30 primarily for warranty purposes (the older cars I have - I30s and 97Q require 5W-30 or 10W-30). I never have had a VH45 which allows up to 20W-50 grade. The 97Q has a VH41 and only allows 30 grade oil, probably due to tighter tolerances. However, the newer cars (03Q and 06M) do allow 10W-40 oil.

Aside from probable problem with warranty, I’m concerned that the 0W-40 grade which has higher viscosity (@ 14cSt) than xW-30 (@ 10cSt) will worsen my gas mileage (07Q in NorCal – 13city/16combi/21hwy MPG), lower the HP, results in higher engine temp and even prematurely wear engine components (higher than required viscosity=higher friction). Besides, I don’t want to store various grades of oils in my garage.

I have visited multiple sites where used oil parameters are available as well as head-to-head test data. From what I’ve seen, the Mobil xW-30 grade (regular and synthetic) has stable viscosity (10cSt or higher @ 212F), decent HTHS (@ 3cTs @ 302F) and very good TBN (9 or higher). The Mobil 1 0W-40 of course is much better but shears down from 14cSt to 12+cSt before 3000miles, probably bottoms out to <12cSt @ 6000miles and then starts to go up after that (due to oxidation, accumulation of contaminants, etc.).

AMSOIL may be the best in the xW-30 grade but in fairness to Mobil, the 0W-30 from AMSOIL is pure synthetic (Group IV) while Mobil xW-30 is a synthetic blend (Group III base oil plus Group IV and probably Group V). So obviously, a pure synthetic will perform better than a blend. In all the testing presented at its site, AMSOIL never compared their synthetic oil with Mobil’s 0W-40. A certain lab did a dyno test on AMSOIL 0W-30 and Mobil 0W-40 which shows Mobil has 9 HP more than AMSOIL on a given engine @ 5000 RPM.

From what I’ve learned and the fact that our older cars are out of warranty and 40 grades are allowed in our newer cars, I will switch to 0W-40 soon. My new concern would be how my original ‘cats’ will handle the higher level of Phosphorous. I just found out that Mobil 0W-40 (and other High-Mileage formulations) has a high level of this chemical (>1000 PPM vs. Federally mandated limit of 400 PPM on fuel/energy conserving oils) in the ZDDP additive. Too much Phosphorous can damage the catalytic converter.

My current OCI is 4-mo/4000 miles but will extend it to 6-mo/6000 miles once on true synthetic. That’s still conservative considering European cars have recommended OCI of 10,000 miles or more. I will also have UoA (Used Oil Analysis) to see if I need to change the OCI.