0W40 in a 0w20 spec vehicle?

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Originally Posted By: Thax
Dodge 4.7's run best on a thinner oil , dont recommend a 40 weight oil.


I don't think anyone here would "recommend" that 0W-40 be used in this application. The OP was mainly just asking if he can use it without causing problems since he already has it on hand, and the answer is yes. I see you are using 5W-30 in your 4.7. (As did I in the Grand Cherokee with the 4.7) As pointed out, the M1 is a light 40, so it's not much thicker than a 30 at operating temp. Because it's a 0W-40, it will actually be better than a 5W-30 on cold startups when most wear occurs. Since it's already on hand, I would use it up before buying new oil.

(Yes, I'm still a newbie here, but I've done enough reading here and other places over the years to have gained at least a little bit of knowledge)
 
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you could always put the cases on ebay, they will move if priced at a normal price. assuming you bought it at walmart prices or better you could actually break even selling the cases.

After they sold i would buy the correct weight of M1. also if the cases are unopened and SN take them to walmart or and auto store and see if they will trade you 0w20 or 5w20 M1 for the 0w40. i bet walmart will trade you. they take returns and switch outs without recipts.
 
Originally Posted By: KD0AXS
Yes, I'm still a newbie here, but I've done enough reading here and other places over the years to have gained at least a little bit of knowledge


Shouldn't be so modest; you try to learn and offer that advice cautiously. Newbie or not, what you said makes sense, and I can respect your effort
smile.gif


73'
 
Originally Posted By: RiceCake
Originally Posted By: KD0AXS
Yes, I'm still a newbie here, but I've done enough reading here and other places over the years to have gained at least a little bit of knowledge


Shouldn't be so modest; you try to learn and offer that advice cautiously. Newbie or not, what you said makes sense, and I can respect your effort
smile.gif


73'


Sorry, wasn't trying to be a know it all. Just seems that's the way forums work, if you don't have 12,000 posts you don't know anything. (Although here it seems to be a little better)
 
Originally Posted By: KD0AXS
Originally Posted By: Thax
Dodge 4.7's run best on a thinner oil , dont recommend a 40 weight oil.


I don't think anyone here would "recommend" that 0W-40 be used in this application. The OP was mainly just asking if he can use it without causing problems since he already has it on hand, and the answer is yes. I see you are using 5W-30 in your 4.7. (As did I in the Grand Cherokee with the 4.7) As pointed out, the M1 is a light 40, so it's not much thicker than a 30 at operating temp. Because it's a 0W-40, it will actually be better than a 5W-30 on cold startups when most wear occurs. Since it's already on hand, I would use it up before buying new oil.

(Yes, I'm still a newbie here, but I've done enough reading here and other places over the years to have gained at least a little bit of knowledge)


0w40 has a HTHS of 3.8 and a Viscosity of 13.5 at 100c
0w30 AFE has a HTHS of 3.0 and a Viscosity of 10.9 at 100c
0w20 AFE has a HTHS of 2.7 and a Viscosity of 8.7 at 100c

Based on HTHS in particular, there is quite a difference in viscosity from 30 to 40. Certainly much bigger than from 20 to 30. The 30 weight oils that compare to M1 0w40 typically have higher HTHS to meet the European specs that 0w40 meets.

0w40 has MRV of 31000 vs 0w30 AFE MRV of 13250 vs 0w20 AFE MRV of 9200.

Again a much bigger difference between 0w40 and 0w30 than there is between 0w30 and 0w20.

Of course we don't know where the OP lives, and all the manufacturers who spec M1 0w40 say it is suitable for all temps, but the point that the HTHS for 0w40 is too high is still valid. Also, many 5w30's could be better in the cold than 0w40, particularly at non extreme cold temps.

I think this is why some very knowledgeable posters suggested mixing down the 0w40.
 
Well, I went from a Mercedes with 170k on the clock to a Dakota with 30k on the clock for around $10k difference...

I registered in '06 and posted a bit, but dropped off and just lurked. Somewhere in the interim, my account got jacked up so I couldn't log in. Apparently as part of the reset, all my stats are reset [except my join date, it seems..]

As far as the attitude, well, I wasn't aware this was a popularity contest, besides, we can't cuss at each other, so how serious can things get? I normally hang out on forums that *can* cuss at each other, so I suspect my skin is thick enough to survive here... LOL

Back on topic, though, is the 0w40 really that much thicker than 0w20? If I understand viscosity, 0W is 0W, isn't it? The difference I was expecting to hear about was in the upper range... but then, this *is* why I posted, because I am sure y'all know more about this than me.

Ok, I typed the above before I read the whole thread. I guess I will just use it for my '00 Durango [4.7, 185K miles] and my bike... I got it at oreily and yes, it was a decent price, but selling oil on the internet seems overkill.
 
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Yes no need to sell it. You could use it straight if you're in a fairly warm climate, or blend it with a 0W20 if not. BTW. What region are you from (or what type of climate at least).

In a warm climate I wouldn't be worried in the slightest about the M1 0W40 actually damaging the engine. Fuel economy may suffer a little bit, but not as much as some people think, maybe half of a MPG.
 
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M1 0W-40 is a bit thin for a 40w anyway. No problem at all to use it as long as you don't live in the frozen tundra.

it's an extremely highly rated oil that carries a ton of mfgr certifications. May be the most I've ever heard of on any single can.
 
Originally Posted By: barrysuperhawk
I just traded cars and switched from a AMG mercedes to a Dodge Dakota. Looking at the spec's for the Dakota [4.7 V8] it asks for 0w20. I happen to have a metric ton of 0W40 Euro spec Mobil1 left over from the mercedes, [like 6+ cases] and all of my oil analysis seems to point to this oil being some of the best Mobil1 makes.

Is there any reason I wouldn't be able to use the 0w40 in place of the 0w20?


21.gif


I am NOT trying to be a jerk but I am just curious where you came up with the Dakota w/ the 4.7L spec'ing 0W20? Prior to 2007 the Dakota's with the 4.7L spec'd 5W30. Starting in 2007 the oil spec was 5W20. Never heard of Chrysler spec'ing 0W20 in a 4.7L( or any vehicle actually? ). They didn't even give an option for 0W20.

Dakota 4.7L oil weight spec's:
2006 and earlier 4.7L = 5W30
2007 4.7L & 4.7L HO = 5W20
2008 4.7L & 4.7L HO = 5W20
2009 4.7L & 4.7L HO = 5W20
2010 4.7L = 5W20
2011 4.7L = 5W20

Not saying 0W20 is bad or anything. Just not the "spec'd" weight. I personally would not run the 40 weight. I would get some 5W20 or 5W30 depending on what year this Dakota actually is and run the called for weight. JMHO.
 
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Originally Posted By: KD0AXS
Just seems that's the way forums work, if you don't have 12,000 posts you don't know anything. (Although here it seems to be a little better)


So many people confuse talking a lot with having a lot to say...

If it were me, I'd mix it with something to bring it down to the 30w's. Or trade it. Or sell it. It's only oil.

However, on the other hand, you should be able to use it without much trouble unless there are considerations of which we are unaware.

My Prius C maintenance booklet is ADAMENT that I use 0w-20. However, another Prius Chat member from Singaport provided us with information that his area C's can use: 0w-20, 5w-20, 5w-30, 10w-30, 15w-40, and even 20w-50! The 20ws's and 5w-30 are good from -20*F to 100+*. The 10w-30 is good starting at 0*F. The 15w-40 is good from 10*F. And the 20w-50 is good from 20*F.

I would say you could use it if it pleases you.
 
Some engines that are spec for thinner oils actually do much better with the 0w40 eg the Nissan VQ engines.
I see no problems whatsoever running it right out of the bottle in your engine. Try it you might like how the engine runs and sounds.

Don't buy into the "oil pump will go into into bypass" with anything thicker than light oil in the sump talk, at best its somewhat inaccurate and when then certainly not with 0w40/5w40.
 
Originally Posted By: barrysuperhawk
Well, I went from a Mercedes with 170k on the clock to a Dakota with 30k on the clock for around $10k difference...

I registered in '06 and posted a bit, but dropped off and just lurked. Somewhere in the interim, my account got jacked up so I couldn't log in. Apparently as part of the reset, all my stats are reset [except my join date, it seems..]

As far as the attitude, well, I wasn't aware this was a popularity contest, besides, we can't cuss at each other, so how serious can things get? I normally hang out on forums that *can* cuss at each other, so I suspect my skin is thick enough to survive here... LOL

Back on topic, though, is the 0w40 really that much thicker than 0w20? If I understand viscosity, 0W is 0W, isn't it? The difference I was expecting to hear about was in the upper range... but then, this *is* why I posted, because I am sure y'all know more about this than me.

Ok, I typed the above before I read the whole thread. I guess I will just use it for my '00 Durango [4.7, 185K miles] and my bike... I got it at oreily and yes, it was a decent price, but selling oil on the internet seems overkill.



i would exchange them at orielly for 0w20 0r 5w20 personally. ultimately what you decide to do with it is your decision. personally i see no benefit to the 0w40 in your application,id rather run a 20wt, but i do not think the 0w40 will be any harm. it will be as light on start up as many 20wts, but way thicker at operating temperature, which will be ever so slightly less efficient.
 
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If they'll exchange it, that's definitely the way to go. If it was purchased recently, they likely would exchange it. I don't know exactly what "a good price" means, but if it was bought on clearance it's doubtful that they would exchange it.
 
Originally Posted By: NHGUY
Went from a Mercedes to a Dodge Dakota? That should show them Germans!(Daimler once owned Chrysler in a bid to fleece and destroy the company).I would take 5 Dakotas over 1 Mercedes,Dr Z sickens me.



Eh Yeah, I`m sure they intentionally set out to destroy Chrysler on their dime. Do you realize how stupid that sounds? ( I`m not calling you stupid, but a silly post)
 
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I've been running 40 grades in my mustang since I got it. My cams looked like new with 140000kms on them. I doubt very much you are going to do anything bad to your engine using a 40 grade over the spec'd 20 grade. You may lose a couple mpg though.
I would use up your stash. It's one of the best oils on the planet. If you are really concerned mix it with a 20 grade. Preferably the same brand
 
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