High oil temp while towing: need more PAO/Ester, or more viscosity?

[LubricatusObsess]

Originally Posted by blufeb95
Originally Posted by MolaKule
Or, use a 5W20 which has less VII and uses slightly higher viscosity base oils.

I'm not sure if that's necessarily the case with mobil1 EP, the 0w20 is like 60-70% PAO on the SDS, the 5w20 is only 5-10%, I assume the rest is probably hydrocracked dino if they don't specify. Since there's so much PAO in the 0w20 isn't it possible that since it uses a presumably higher quality base oil that it might actually have a lower VII content than the 5w20 variant.


I'm surprised Mobil reveals the % API Base Stock Groups on their SDS.
Anyway, the question becomes what is OP is looking for? OP concern is higher engine coolant temps at high load. What oil is needed? Well, high load = high HTHS. High temp = oxidation resistance. (NOACK, TOST, etc.). I believe Gokhan has shown that Group IV oils may not always by the highest HTHS / HTFS. I'd start with his chart first.

The best of the Mobil 1 bunch (highest HTHS & HTFS & Lowest VII additive) is Mobil 1 EP HM 5W-20. I can't post a screen photo of his chart.

 

[390pi]

I agree with a previous post: check oil temp with an IR thermometer.

It would help to confirm that you are probably fine with the 0w20.

Its a good tool to have anyway.

 

[CKN]

Originally Posted by zuluplus30
2017 Silverado 5.3 towing 7.5k on a routine basis now. Coolant temps hold at 207, then up to 215-220 until the fans pull it back to 207. I notice when I stop, the oil psi drops to
My question is keep running 0w-20 Dexos (Currently on M1EP) and stay with a higher PAO/Ester oil, or step up a grade to 0w-30/5W-30 for the higher HTHS? I don't give 2 squats about MPG. This is purely for wear protection.

Edit: Almost out of powertrain warranty so viscosity in regards to warranty are moot.


I tow all over the Rocky Mountain West (2018-5.3 Silverado) up very high mountain passes it appears that are not in your part of the country without issues-using what the manual recommends 0/20w. You are searching for a solution to a problem that doesn't exist.

 

[chainblu]

I don't think 19-20 psi at idle is that low, especially during a heavy tow. Personally, I'd be more concerned where my pressure was while driving.

With 71K members in BITOG, we could conjecture this to death. There really is only one way to find out. My guess is that stepping up just one grade isn't going to be much different.

 

[RDY4WAR]

I lean toward adding an oil cooler and/or higher capacity oil pan with a more thermally stable oil as opposed to increasing oil viscosity.

 

[krismoriah72]

"I don't give 2 squats about MPG. This is purely for wear protection"

If you want to read Pennzoils answer... https://www.pennzoil.com/en_us/education/know-your-oil/0w-viscosity-faqs.html


"if you have a car that recommends 0W-20, do not use 5W-30 - back # of vis-grade must match or it is a no-go."

", if your owner's manual calls for a thicker oil, you should not use a thinner SAE grade nor use a thicker oil for a recommended thinner oil vis-grade."


Later on they say

"After the warranty period, a car that calls for SAE 5W-20 engine oil can use SAE 0W-20 motor oil because the second number (20) is the most crucial number for suitability. Pennzoil's 0W synthetic motor oils offer the same protection as SAE 5W and gives the additional benefits of faster flow at start-up, enables faster engine warm up and delivers better fuel economy."



So in summary.. even Pennzoil doesnt know.

 

[OilReport99]

VAS 5w-20, and if willing to spend a bit more, Redline 5w-20.

 

[westcoaster]

I have a Hemi Ram and it has a spec for 5W-20. But in the manual it also states that 5W-30 is also acceptable. I also tow my travel trailer quite regularly and I'm in a valley so I have a bunch of steep hills to climb out of when we go anywhere. I run the Rotella 5W-30 T6 with no issues. A well known robust oil that can take high temp extremes. It's a little low on moly so I give it a good slug of the MOS2 to bolster it. Maybe a solution if your worried about oil temps and thrashing the 5W-20.

 

[zfasts03]

I am curious to see what oil temps. you are seeing by checking with an IR thermometer. If oil temps are under 250 degrees F. I think your are fine. If your see over 250, I think you are overworking the driveline. Also keep an eye on transmission temps, which can be viewed on the Drivers Info. Center.

 

[PimTac]

1. There are no oils that are 100% PAO. It's not possible and it's not a good idea either.

2. There was no lawsuit.

 

[ChristianBerg]

Originally Posted by PimTac
1. There are no oils that are 100% PAO. It's not possible and it's not a good idea either.

2. There was no lawsuit.

1) I already understand that
2) same
3) why can't we all get back to the thread topic?

 

[OilReport99]

Originally Posted by ChristianBerg
Originally Posted by PimTac
1. There are no oils that are 100% PAO. It's not possible and it's not a good idea either.

2. There was no lawsuit.

1) I already understand that
2) same
3) why can't we all get back to the thread topic?


Let's do that

 

[Gene K]

The answer is no.

But if it makes you feel better go with an oil like Castrol Magnatec 5W-30 that is known to resist shearing.

It's likely a GIII but if your actually concerned about viscosity I would worry more about what works.

 

[userfriendly]

......."or more viscosity?"

Delo 400 ZFA 10w30 FA-4, SN, SN plus

40C 65
100C 9.8

 

[oldhp]

In the summer, or all year, I would use this and be done with it.

Red Line 0W20

ACEA Service Class A5 B5
API Service Class SN/SM/SL/SG/CF
SAE Viscosity Grade (Motor Oil) 0W20
Vis @ 100°C, cSt 9.1
Vis @ 40°C, cSt 48
Viscosity Index 172
CCS Viscosity, Poise, @ °C 55@-35
Pour Point, °C -60
Pour Point, °F -76
NOACK Evaporation Loss,1hr @ 482°F (250°C), % 9
HTHS Vis, cP @150°C, ASTM D4741 2.9

 

[domer10]

Why not run a oil like RTG considering it was formulated with additives tailored to what you do exactly. Run 5w20. One of best oils I have run I my Jeep, with noticeable differences, not just placebo effect.

 

[Bryanccfshr]

If you care about wear protection step up the viscosity. Higher viscosity provides greater water protection period.

 

[vivaUkraine]

In my old 4.2 L V8 Mercedes engine, the hot oil pressure at idle is usually around 1.5 bar. On a hot day, after 40 minutes of driving it drops to 1.2 or even 1 bar when it's 90F+ outside - at idle. In heavy mountain climbing it may drop to 0.8 bar - at idle. That's on 229.5 5W-40 oil. Owners manual states as low as 0.3 bar is acceptable. I'm pretty sure your 20 psi (about 1.5 bar) after towing is COMPLETELY normal. Dig into your owners manual, it should say somewhere what is the lowest acceptable hot idle oil pressure

 

[ZeeOSix]

Originally Posted by chainblu
I don't think 19-20 psi at idle is that low, especially during a heavy tow. Personally, I'd be more concerned where my pressure was while driving.


Yeah, I wouldn't be too concerned with 20 psi oil pressure at idle with hotter than normal oil. Oil pressure is just an indication of the flow volume at a certain viscosity. At the same flow volume, the pressure will obviously have to go down with thinner oil.

The sole purpose of an oiling system is to distribute an adequate oil volume to all parts of the engine. The oil pressure really doesn't play much, if any role in adding more MOFT in journal bearings. As long as the required volume is supplied then the parts are lubricated. However, it's the viscosity and RPM that are the main factors for protection from wear. Lugging an engine with high throttle load and at low RPM makes the MOFT even smaller - giving more chance of metal to metal contact and wear.

Bumping up a viscosity grade certainly isn't going to hurt because you will get more MOFT and HTHS with a thicker grade, which will give you better wear protection, meaning more headroom in MOFT, the only thing that keeps moving parts from touching.

OP - can you see the engine oil temperature through an good OBD2 scanner? Decision to bump up to a xW-30 could be better determined if you knew the max oil temp.

 

[avi1777]

if there a problem you can use a high hths oil,install an oil cooler and a bigger sump.but since u dont
i would just use a super tough oil like redline 5w30 and thats it.