Using 10W-30 over 15W-40 & 5W-40

[-SyN-]

I’m curious of the number of actual on-road Diesel engine owners whom would on your next OCI not hesitate to pour in a 10W-30 viscosity over the 15W-40 or 5W-40 that you just drained out?

For basically year round use - not just for the winter months.

No long drawn out arguments intended here just kind of a survey or show of hands.
I know a few within these walls have posted many times - extremely good results running a 10W-30 viscosity oil in a modern on-road diesel motor. Thus the reason for my question.

Yes I am thing about it within my 2017 Ram 6.7L CTD.
I contacted my service mgr about running Schaeffers Ultra 10W-30 yr round & he gave me 2 huge Thumbs up.

Thanks
Lonnie

 

[skyactiv]

Don't rely on what your service manager says, rely on your owners manual. Remember, FCA pays for all warranty work and your dealer wont back you
if FCA denies a warranty due to using the wrong viscosity.

 

[beanoil]

10w30 in my 2003 F250 6.0 diesel for the time I owned it.
15w30 in my 2016 F250 6.7 diesel now and for a long time to come.
Both primarily used for towing, very little grocery getting.

 

[Artem]

My Kenworth semi truck specs 10w30 for the Paccar engine. I poured in 15w40 and noticed quieter engine chatter vs before.

Having said that, you could easily get away with a shear stable 10w30. The only concern I'd have is the oil shearing down a degree and be to thin @ say... w20 by the end of your interval.

 

[Audios]

Im running Motorcraft 10/30 Super Duty Diesel in the TDI right now, it has been on my mind since its a 10/30, but I guess thats the Bitoger in me. I cant wait for the analysis just to see whats going on with the different viscosity. Ive ran 5/40 since I bought it, I only tried it out since WorldPac listed the price incorrectly and honored a 13$ 12 pack of it.

 

[bullwinkle]

I've been using T5 10W30 in the 6.2, both for winter starts and possibly a (tiny, immeasurable) increase in MPG. My Ram gets 5W40, mainly because I have a pretty good sized stash of M1 TDT, Delvac 1, and ESP from multiple closeout sales & (too good to pass up) rebate deals. My only concern, on an in-cylinder enriched DPF system, is fuel contamination-that is what would be my only problem with 10W30 in a DPF equipped Cummins. I even watch my oil level like a hawk on my 5.9!

 

[SavagePatch]

Does a 10w30 Synthetic Blend really provide better cold starts than a 5w40 Full Synthetic?

Let's say on a cold snowy morning about 28°F...

*And yes, I know that 28°F isn't extreme cold but I wanted to use an average temperature that many members might be seeing.

 

[TiredTrucker]

I have a factory remanned Detroit 60 12.7. I use a Schaeffer 10w30 syn blend in it, year round. I now have 869,000 miles on the reman. Oil samples still as good as when the motor had 50,000 miles on the reman. Only uses about 2 qt of oil between oil changes of around 22,000 - 23,000 miles / 450 hours (50% longer than OEM recommended oil change interval of 15000 mile / 300 hrs for the Series 60 pre-EGR). Motor is all original and will easily exceed 1 million miles.

A 10w30 is not going to provide a better cold start than a 5w40. it will over a 15w40. But when things get that kind of cold to make a difference, I also use a oil pan warmer that keeps the oil warm and the motor starts like a warm summer day in the dead of winter. I usually will keep the sump warm on nights where the truck will sit all night turned off and the temps get below 0F.

I found the motor does not beat up the 10w30 nearly as bad as the 15w40 I used early on. Brand didn't make a difference. I have also used the Delvac Extreme syn blend 10w30 in this motor and gotten similar results as with the Schaeffer 10w30. Actually, the UOA's looked virtually identical across the board.

The lubrication manuals of all the major brands of on road heavy diesel engines allows for using 10w30. So worrying about OEM recommendation is not an issue. Dealers and their shops are not OEM recommendations. Even on my 2000 MY factory remanned Detroit 60. 10w30 was recommended by my Schaeffer rep, it was allowed by the Lube manual for my motor, and I gave it a try. I am convinced it is more than up to the challenge.

 

[BrianF]

I am in the same boat so I did some reading. I am running PetroCanada Duron SHP semi synthetic 10w30 in my Ram since pouring the factory fill. I am on the second fill now of the Duron. This oil has better cold flow properties than the conventional 10w30 I have seen and better than T5 and Citgo 10w30. Yes it is 10w so it is not the same as 5w but the cold flow is close to that of a fully synthetic 5w40. Remember it is a thinner oil all around. Is it going to cause more start up wear than a 5w40 in cold climates? Maybe, but I have yet to see any real data showing reduced engine life. I am not worried as when it gets really cold up here I plug in the block heater. Many people run 15w40 conventional year round up here and their engines have yet to blow up. If I lived in an even colder climate, with even longer winters, then yes I would start looking at a different oil. I would look at PetroCan's 5 and 0w30 oils. Now those have some nice cold flow numbers.

Yes the manual for the Ram stipulates 40 weight oils but their caveat is you can use CES 20081/86 oils. Cummins themselves approved some 30 weight oils... what Duron SHP 10w30 is one of them? Perhaps FCA will give me grief on warranty, perhaps not.

I posted the first UOA on my Ram in the UOA section. Its too early on the judge wear metals but the oil held up well in its 24,000km index, with close to half of it towing (48,000km on the truck). Its viscosity held up quite well, even with a decent helping of fuel dilution and the additives were strong. Once I gather more data as the miles add up, I plan on extending my oil changes.

Oh in the case of Duron, the 10w30 is 3$ a liter cheaper than the fully synthetic 5w40. Oh but oil is cheap insurance.

 

[TiredTrucker]

Heck, Cummins via it's in bed partner, Valvoline, makes a 10w30 HDEO that it approves of for all the motors. It meets CES 20081/86. Actually, a stack of 10w30 oils including a 5w30 HDEO on the approved CES 20086 list.

Cummins stipulates 20086 for you ride because of DPF and SCR issues. CK-4 (CES 20086) was made specifically for that. Any quality CK-4 oil can be used in that motor. Now, Cummins specs and factory fills it's big liter engines up thru the ISX with 10w30. It seems quite a stretch for anyone to think that 10w30 wouldn't work just as well in the ISB of the Ram pickup.

 

[roadrunner1]

In my '15 6.7 Powerstroke it has had nothing since factory fill(10w-30) but 10w-30 Deere Plus 50 II, and I'm just short of 90,000 mi. UOA's have shown low wear rates and viscosity holding in the upper 30 wt. range. I run it out until the IOLM says "change oil now", which during the summer is 10,000 mi., and winter commute is closer to 7,500 mi.

I previously had an '07 6.0 PowerStroke that I kept until approx. 210,000 mi. with 10w-30 starting at roughly 85,000 mi., UOA data always came back excellent with that truck also, running 7,500 mi. OCI as specified per the manual.

 

[userfriendly]

How thin can you go with light truck Diesels? With a 6 speed or more automatic transmission. I'll guess around 2.7 HTHS to be safe.

 

[-SyN-]

Besides extreme cold weather & possibly a little bit better fuel economy: What was the main reasoning for using the 10W-30 viscosity in theses on-road Diesel engines?

Was it strictly for cold weather pump ability?

Thanks for the replies fellas: Please keep them coming!

Main reason for my question is years ago when I had my 2001 7.3L PSD: I made the switch one winter from 15W-40 too Rotella T6... I was shocked at the difference it made in the engine on those cold mornings starting up. But. With that said my glow plugs were a little tired as well as the injectors so I know that thinner viscosity made life a little easier on both of them.

I never went back to 15W-40!

As for my Cummins: she is kept in the garage most of the time so cold morning starts will never be an issue. But I still was going to keep running a 5W-40. And I started reading of owners running 10W–30 then I started thinking of any advantage this would offer.

 

[-SyN-]

Never mind with my last post I some what found the answer to my own questions.

 

[BrianF]

Similar cold flow to 5w40, large cost savings and equal protection. Win win.

Another thing I was thinking about with the 30 weight CK4/SN oil is going to a single oil to buy for all my gas vehicles and OPE. I have random jugs of all sorts kicking around and that has to stop.

 

[claluja]

Should be fine, as long as you don't have fuel dilution issues.

If you want to be safe, do a UOA before switching to check viscosity changes or fuel dilution measured by gas chromatography (i.e., ignore any fuel dilution allegations from Blackstone).

 

[TiredTrucker]

Originally Posted By: userfriendly
How thin can you go with light truck Diesels? With a 6 speed or more automatic transmission. I'll guess around 2.7 HTHS to be safe.


Every CK-4 10w30 HDEO is going to have a minimum HTHS of 3.5. Only when one gets into the FA-4 stuff does HTHS get lower, and then that standard is a minimum of 2.9 I believe.

 

[dnewton3]

As most know, I ran dino 10w-30 in my Dmax for a decade. Flogged it many times pulling the RV out west and back.
UOAs were demonstrably boring; but being a Dmax, that's expected regardless what's in the crankcase.

 

[SavagePatch]

Originally Posted By: TiredTrucker
Originally Posted By: userfriendly
How thin can you go with light truck Diesels? With a 6 speed or more automatic transmission. I'll guess around 2.7 HTHS to be safe.


Every CK-4 10w30 HDEO is going to have a minimum HTHS of 3.5. Only when one gets into the FA-4 stuff does HTHS get lower, and then that standard is a minimum of 2.9 I believe.


So... roughly...

15w40 = 4.3
5w40 = 3.8
10w30 = 3.5
FA-4 = 2.9

I've ran consecutively and had UOA's done, for fun, with 0w40, 5w40, and now 15w40 in my Ram EcoDiesel. The UOA's so far have been "boring" (thanks for the new termonology Dnewton). Maybe I'll do a 10w30 next. Not for scientifically definitive data, just for fun.

 

[Dak27]

I also run a 12.7 Detroit Series 60 motor in my semi. I've been using 15W40 Phillips 66 Guardol semi-synthetic for the past few months. Because I pull quite a bit of heavy loads out of Idaho, which put my gross vehicle weight close to 80,000 lbs, I feel better about running a heavier oil for the majority of the year, especially when the outside temperatures are very warm. My loads frequently have me going into Texas and across the South.

I do use 10W30 in the coldest months of the Winter. I'll be using Guardol 10W30, starting in late November. I'll switch back over to 15W40 either in late March or early April. I notice the 10W30 does help for quicker cold weather startups.