Should I run 5w30 in my ram hemi for towing

[SteveSRT8]

We started running 5w-30 in our 14 5.7 RAM at about 50k miles. We only tow a smaller boat with ours, so it's not working very hard.

And no offense but 235-245 is actually a great temp to run most oils at, it will protect you very well. Just use a quality oil.

And I did run a batch of 0W-40 M1 through it. Couldn't really tell any difference at all. Averages just short of 20 mpg if driven normally.

 

[SteveSRT8]

Originally Posted By: SR5
If the MDS has problems with moving from a 20 grade to a 30 grade oil, then how does it work when it's cold ?

M1 0W20 KV100 = 8.7 cSt
M1 5W30 KV100 = 11.0 cSt

But

M1 0W20 KV40 = 44.8 cSt

There is a bigger change in viscosity in going from a temp of 40C to 100C with the same oil than in going from a 20 grade to a 30 grade oil at the same temp.

And these oils get a lot thicker again as they approach freezing and below.



Having owned new gen Hemis in a few versions now I can say without reservations that the Hemi/MDS must have 20w thing is greatly overstated. Modern hemis run well on almost any normal oil and generally last quite a long time.

 

[demarpaint]

Originally Posted By: JohnnyJohnson
Well I'd run this Mobil 1 that is on Rollback.

https://www.walmart.com/ip/Mobil-1-0W-40-Advanced-Full-Synthetic-Motor-Oil-5-qt/23636902

That is another good choice.

 

[Gokhan]

Originally Posted By: Jaymie
Interesting, is that because it won’t flow as quickly?

No, thicker motor oil runs hotter because higher HTHS viscosity (HTHSV) causes more friction in the bearings. That is why the fuel economy drops with the increasing HTHSV.

From your oil temperatures (convert them to C first so that they would be useful) -- 102 C without towing and 112 C with towing -- definitely go with 5W-30 for towing. It would give an extra margin of safety for towing. There is probably no need for 0W-40 unless you want to do extreme towing.

You can play around with the Widman calculator for the operational viscosity. Just plug in the KV40 and KV100 values from the data sheets.

https://www.widman.biz/English/Calculators/Operational.html

That doesn't take into account the need for higher viscosity (particularly HTHSV) because of more load in the bearings but at least it takes into account the oil temperature.

Here is the fundamental curve of lubrication -- Stribeck curve -- that tells you what happens when you change the HTHSV (n [eta]), load (P), and RPM (v). In the bearings you want to stay in the hydrodynamic-lubrication region:

 

[irv]

I've always stuck with 5W-20 but I don't tow anything near the weight the OP does.

The manual, at least prior to the 2019's, read this:

Quote:
Engine Oil Viscosity — 5.7L Engine (1500/2500/3500 Models)
MOPAR SAE 5W-20 engine oil or equivalent Pennzoil® or Shell Helix® is recommended for all operating temperatures.

NOTE: For 2500/3500 trucks with a 5.7L engine operating under a gross combined weight rating of 14,000 lbs (6 350 kg) or greater, SAE 5W-30 engine oil is recommended for all operating temperatures.

Stick with the Pennzoil.

 

[sloinker]

This is what I would use.
https://www.ravenolamerica.com/categorie...make/dodge.html

 

[bbhero]

Very, very good post SR5.

 

[bbhero]

And very, very good post and information gokhan.

 

[BrianF]

I wish I had done some UOA on my 2011 Ram 1500. I ran 5w20 for the 145,xxxkm I had it. Varied between PPPP, Motomaster, QS and some Mobil. I ran it hard while towing. Usually the oil temp was around the 105 C mark but on some heavy passes it was up to 115 C. I did 10-12,000km oil changes and did a Fram Ultra every second change. It didn't smoke, knock or burn anything within that index. I cant say for certain the engine was fine as I have no empirical evidence to say that but I have no evidence to say otherwise.

I am glad I moved up to a diesel but that Hemi could really get that truck moving.

 

[CT8]

5W-30, 0 w-30 , 0W-40

 

[s2krunner]

Originally Posted By: SilverSnake
The Hemi requires 5W-20 for proper operation of the MDS. Go by what the book says. These forum members that don't own or drive a Hemi will not be there when your engine warranty work is denied because you are using the wrong weight oil. It would be a good idea to change out the factory fill and go with the Penzoil Platinum or Ultra Platinum ASAP. I have owned many Hemi's and have done so for each one. For your application I would change out the oil every 6 months or 5K miles.


Are you running Pennzoil because book says so?

 

[dave1251]

Originally Posted By: SilverSnake
The Hemi requires 5W-20 for proper operation of the MDS. Go by what the book says. These forum members that don't own or drive a Hemi will not be there when your engine warranty work is denied because you are using the wrong weight oil. It would be a good idea to change out the factory fill and go with the Penzoil Platinum or Ultra Platinum ASAP. I have owned many Hemi's and have done so for each one. For your application I would change out the oil every 6 months or 5K miles.


One warranty work will not be denied for using a proper spec 5W30. Two MDS is not affected by using 5W30. Three I use 5W30 in my 5.7 and will continue to do so. Four it is very irresponsible to spout off false information with faulty knowledge at best.

 

[rossn2]

Yes, run the 5w-30, it's even in your owner's manual to use it when towing!
That's what I run here in TX and tow an enclosed trailer..

 

[Ram02]

5w30 should provide better protections

 

[e55amgbenz007]

Originally Posted By: Gokhan
Originally Posted By: Jaymie
Interesting, is that because it won’t flow as quickly?

No, thicker motor oil runs hotter because higher HTHS viscosity (HTHSV) causes more friction in the bearings. That is why the fuel economy drops with the increasing HTHSV.

From your oil temperatures (convert them to C first so that they would be useful) -- 102 C without towing and 112 C with towing -- definitely go with 5W-30 for towing. It would give an extra margin of safety for towing. There is probably no need for 0W-40 unless you want to do extreme towing.

You can play around with the Widman calculator for the operational viscosity. Just plug in the KV40 and KV100 values from the data sheets.

https://www.widman.biz/English/Calculators/Operational.html

That doesn't take into account the need for higher viscosity (particularly HTHSV) because of more load in the bearings but at least it takes into account the oil temperature.

Here is the fundamental curve of lubrication -- Stribeck curve -- that tells you what happens when you change the HTHSV (n [eta]), load (P), and RPM (v). In the bearings you want to stay in the hydrodynamic-lubrication region:

Wait, I am lost here. Engines, such as the European variety that require a higher HTHS film strength are actually increasing the friction/wear with the requirement?

 

[SilverSnake]

I run Penzoil because IMO opinion it is as good as it gets.

 

[SilverSnake]

Originally Posted By: dave1251
Originally Posted By: SilverSnake
The Hemi requires 5W-20 for proper operation of the MDS. Go by what the book says. These forum members that don't own or drive a Hemi will not be there when your engine warranty work is denied because you are using the wrong weight oil. It would be a good idea to change out the factory fill and go with the Penzoil Platinum or Ultra Platinum ASAP. I have owned many Hemi's and have done so for each one. For your application I would change out the oil every 6 months or 5K miles.


One warranty work will not be denied for using a proper spec 5W30. Two MDS is not affected by using 5W30. Three I use 5W30 in my 5.7 and will continue to do so. Four it is very irresponsible to spout off false information with faulty knowledge at best.


One: Unless you plan to be there and cover my repair costs if the warranty is denied then your comment is meaningless.
Two: My book says 5W-20 is required for proper operation of the MDS. I do not care what you say.
Three: I don't care what you use in your 5.7L
Four: So you think recommending that someone go by the book is irresponsible and constitutes false, and faulty information? It is difficult to find the words to respond to such an idiotic comment without violating the rules of this forum. So, I won't even try.

 

[glock19]

I'm a by the book kind of guy. If the manual says 5w-20 then that's what I'd run. I don't pretend to know more than the engineers who built the truck.

If you're having trouble with oil temps, why don't you look into an engine oil cooler?

 

[billt460]

Originally Posted By: SilverSnake
One: Unless you plan to be there and cover my repair costs if the warranty is denied then your comment is meaningless.
Two: My book says 5W-20 is required for proper operation of the MDS. I do not care what you say.
Three: I don't care what you use in your 5.7L
Four: So you think recommending that someone go by the book is irresponsible and constitutes false, and faulty information? It is difficult to find the words to respond to such an idiotic comment without violating the rules of this forum. So, I won't even try.


This ^^^^^^^^

All I use in my 2015 5.7 HEMI is 5W-20 Pennzoil Platinum Full Synthetic. And it is all I will ever use. It is what the manufacturer recommends for proper operation of the MDS system. Why would I use anything else? Because someone on BITOG thinks I should because they do, and have managed to get away with it so far? That is the most idiotic thing I have ever heard.

 

[billt460]

Originally Posted By: SR5
If the MDS has problems with moving from a 20 grade to a 30 grade oil, then how does it work when it's cold?


It doesn't. The MDS system remains inactive until the engine and oil reach operating temperatures.