Oil Preference?

[HSKR R/T]

No, I dont believe I am saying that at all. For example, My wifes porsche Macan 2.0 uses the VW ea888 engine. It started life with a 5w40 (porsche a40) oil weight recommendation and is now recommended to use 0w20 (porsche c20). it is literally the exact same motor, internals everything the same. Its not that crazy to go from 5w20 to 5w40.

Saying the type of oil you use in a different manufacturers engine should be good for the Hemi isn't a very compelling argument. At least in my scenario, I was at least talking about other Chrysler engines.

You have zero proof that using 5w-20 or 0w-20 is actually bad for the engine other than anecdotal opinion based on what you have used in other vehicles.

 

[HSKR R/T]

That makes sense to me regarding 0W-20 and 5W-20, agree with that assessment.

Though I'm wondering about 5W-20 itself, which I believe was the spec starting in 2009 with the revised 5.7L. Does a higher oil weight beyond 5W-20 improve longevity, I don't think I've seen any proof of that yet.

Technically 5w-20 has always been the recommended oil viscosity for every modern Hemi.made with MDS. The original Hemi used by Dodge in the Rams up to 2009 didn't have MDS.

 

[SD Rebel]

Technically 5w-20 has always been the recommended oil viscosity for every modern Hemi.made with MDS. The original Hemi used by Dodge in the Rams up to 2009 didn't have MDS.

Yup, I think in 2003 the 3rd gen 5.7L Hemi came out in a Dodge RAM using 5W-30, when the first revision with MDS and variable valve timing they switched to 5W-20 in 2009/2010

 

[Ramguymario]

Technically 5w-20 has always been the recommended oil viscosity for every modern Hemi.made with MDS. The original Hemi used by Dodge in the Rams up to 2009 didn't have MDS.

Yup, I think in 2003 the 3rd gen 5.7L Hemi came out in a Dodge RAM using 5W-30, when the first revision with MDS and variable valve timing they switched to 5W-20 in 2009/2010

BMW spec'd 5w-30 and 10w-60 for the same VANOS systems. ram does the same with 5w-20 and 0w-40. VVT has worked better with slightly higher weight oil in every vehicle I have ever owned.

 

[HSKR R/T]

Yup, I think in 2003 the 3rd gen 5.7L Hemi came out in a Dodge RAM using 5W-30, when the first revision with MDS and variable valve timing they switched to 5W-20 in 2009/2010

The Hemis in the 2005+ 300, Chargers, Magnums and Challengers has always been 5w-20 since they always had MDS. So I guess one could use that to argue that is was for fuel economy reasons, as that's why they use MDS. But was the fuel economy a result of lower viscosity oil, or is the lower viscosity oil required as a result of the MDS, and not for fuel mileage.

 

[SD Rebel]

BMW spec'd 5w-30 and 10w-60 for the same VANOS systems. ram does the same with 5w-20 and 0w-40. VVT has worked better with slightly higher weight oil in every vehicle I have ever owned.

On my previous E90 M3, I had the crankshaft bearings replaced at 90,000 miles, and the shop recommended a drop to 5W-50 for better lubrication. I know some E90 M3 guys who dropped to 0W-40 with great oil analysis reports. I haven't done that, 5W-50 seems to be the sweet spot for these older E90 M3 V8s.

But again, that's personal anecdotal. I want to see something that says our modern 5.7L Hemis will do better with a thicker oil before I would consider the switch. I also need it to be Chrysler certified, since I DIY my oil changes and I don't want any service department trying to wiesel out of a engine warranty because I used non-approved oils.

 

[Ramguymario]

On my previous E90 M3, I had the crankshaft bearings replaced at 90,000 miles, and the shop recommended a drop to 5W-50 for better lubrication. I know some E90 guys who dropped to 0W-40.

But again, that's personal anecdotal. I want to see something that says our modern 5.7L Hemis will do better with a thicker oil, otherwise I'm sticking with the recommendation.

100% agree redline 5w50 is s65 heaven

 

[Ramguymario]

i found this article if you guys wanna geek out at hemi internals/ evolution

5.7L Gen III Hemi Engine

The original hemispherical combustion chamber engine design was introduced with the FirePower name for 1951 model-year Chrysler and was rated at 180 hp. The history of the Hemi is filled with plenty of memorable highlights such as Richard Petty’s dominance at the 1964 Daytona 500 where he lapped...

www.enginebuildermag.com

 

[SD Rebel]

i found this article if you guys wanna geek out at hemi internals/ evolution

5.7L Gen III Hemi Engine

The original hemispherical combustion chamber engine design was introduced with the FirePower name for 1951 model-year Chrysler and was rated at 180 hp. The history of the Hemi is filled with plenty of memorable highlights such as Richard Petty’s dominance at the 1964 Daytona 500 where he lapped...

www.enginebuildermag.com

Awesome, I'll take a read after dinner, thanks for posting!

 

[Ramguymario]

I firmly believe that oil weight should compliment bearing clearances. I sourced the specs for the latest gen hemi engine, main bearing tolerances are 0.023 - 0.051 mm . This link provides a comprehensive guide to appropriate viscosity per in relations to tolerances. please reference iron block main bearing recommendations and compare with the ram hemi below. At over 104c temps, given the hemi main bearing clearance, 5w20 is the acceptable lowest weight we can run, 5w40 would be at the higher end. It seems 5w30 is a sweet spot for greater temp ranges.

Now I can only assume that mds is unaffected by oil viscosity as the 6.4 mds is supposedly (according to forums) the same as the 5.7.

my references are below..

https://aaoil.co.uk/wp-content/uploads/2019/05/Driven_BearingClearance_Flyer-803x1024.jpg

https://f01.justanswer.com/StevenA35/5ef130d5-4ee8-4289-af54-0e4d43d21554_5.7_clearances.pdf

 

[SD Rebel]

I firmly believe that oil weight should compliment bearing clearances. I sourced the specs for the latest gen hemi engine, main bearing tolerances are 0.023 - 0.051 mm . This link provides a comprehensive guide to appropriate viscosity per in relations to tolerances. please reference iron block main bearing recommendations and compare with the ram hemi below. At over 104c temps, given the hemi main bearing clearance, 5w20 is the acceptable lowest weight we can run, 5w40 would be at the higher end. It seems 5w30 is a sweet spot for greater temp ranges.

Now I can only assume that mds is unaffected by oil viscosity as the 6.4 mds is supposedly (according to forums) the same as the 5.7.

my references are below..

https://aaoil.co.uk/wp-content/uploads/2019/05/Driven_BearingClearance_Flyer-803x1024.jpg

https://f01.justanswer.com/StevenA35/5ef130d5-4ee8-4289-af54-0e4d43d21554_5.7_clearances.pdf

You may also want to consider how the oil actually reaches parts of the engine, in case of the 5.7L, it has a reputation of not oiling well at idle at the top part of the motor. It doesn't generate the same splash oil lubrication that say a GM small block does.

Does thicker oil matter more than the oil actually reaching the harder to reach parts of the motor that say a thinner oil can?

This is the argument for the other side of the coin, and again, I am talking specifically about the Hemi 5.7L and it's lubrication requirements, I don't have any information that states one way is better than the other. But always looking for something definite that can change my opinion.

One of the other things that is keeping me with 5W-20 is my extended 7 year warranty. If I do get an issue with a roller cam or something else these engines are known for, I don't want the service advisor to look at my DIY receipts and say I used the wrong spec oil.

 

[Ramguymario]

I too am under warranty, should I have any engine failures, my euro mechanic creates oil change invoices for me lol. however given my regimen I dont see that happening. if anything, we learn that 5w20 is perfectly fine, anything heavier is 100% personal preference/ availability.

 

[Ramguymario]

You may also want to consider how the oil actually reaches parts of the engine, in case of the 5.7L, it has a reputation of not oiling well at idle at the top part of the motor. It doesn't generate the same splash oil lubrication that say a GM small block does.

Does thicker oil matter more than the oil actually reaching the harder to reach parts of the motor that say a thinner oil can?

This is the argument for the other side of the coin, and again, I am talking specifically about the Hemi 5.7L and it's lubrication requirements, I don't have any information that states one way is better than the other. But always looking for something definite that can change my opinion.

One of the other things that is keeping me with 5W-20 is my extended 7 year warranty. If I do get an issue with a roller cam or something else these engines are known for, I don't want the service advisor to look at my DIY receipts and say I used the wrong spec oil.

as per oil reaching the top of the motor, our gen hemi engine has the beefier oil pump by 25%. perhaps thats enough but who knows

 

[SD Rebel]

I too am under warranty, should I have any engine failures, my euro mechanic creates oil change invoices for me lol. however given my regimen I dont see that happening. if anything, we learn that 5w20 is perfectly fine, anything heavier is 100% personal preference/ availability.

Lol, that's a cool contact to have in case the dealer tries to stiff you.