Why 10w30 for winter?

[Bambam]

OK I have only had my diesel a year and a half,been running a synthetic 5w40. Because I can't fully utilize a synthetic to make it cost effective I am gonna run conventional oil. So I am not worried about the 15w40 oil for warm weather months,but I am concerned about winter oil. I see the benefit of dropping to a 10w for better pumpability when cold,but what about the hot number? If a w40 is the spec hot number what would be the reason it's not needed for winter? Engine will operate at it's normal temp like always,right? So why thin out the top end? Why not a 10w40 HDEO,assuming one exsists,if not why isn't there one?

Thanks

 

[LateArrivalforLSU]

The film strength of a 30W is usually more than sufficient at operating temp. I would recommend a 40W year round if you tow heavy loads.

Check out my used oil analysis in the diesel section while running 10w30 Rotella.....wear looks very good.

 

[D-Roc]

Originally Posted By: Arkapigdiesel
The film strength of a 30W is usually more than sufficient at operating temp. I would recommend a 40W year round if you tow heavy loads.

Check out my used oil analysis in the diesel section while running 10w30 Rotella.....wear looks very good.


Agreed...there are just a few of us around (like me) who are still having a tougher time making the jump to a 30, due to warranty, or oem requirements. I, for one, am leaning towards the 30 weight HDEO's, though.

 

[Quattro Pete]

Quote:
Why not a 10w40 HDEO,


Aren't mineral 10w-40 oils packed with VIIs which tend to break down over time and leave nasty deposits? Or is this a thing of the past?

 

[Bambam]

Originally Posted By: Arkapigdiesel
The film strength of a 30W is usually more than sufficient at operating temp. I would recommend a 40W year round if you tow heavy loads.

Check out my used oil analysis in the diesel section while running 10w30 Rotella.....wear looks very good.


OK, to my layman's eye it is a very nice report,but

I see you ran it in summer time,could there be any negative affects with cold weather?

Sorry about all this wishy-washy unsuredness,maybe I should stick to synthetic and waste a little money to have piece of mind??

 

[Ken2]

Oil is mainly air-cooled by the air around the oil pan and block. It won't run as hot in the winter unless you're working that engine very hard. I'd stick with the 5W-40 over the winter, and run it the full recommended oil drain interval. An alternative would be to use a 15w40 syn blend.

 

[TiredTrucker]

Or... if you are concerned about oil flow on start up, just do what we did in Alaska and I presently do to all my vehicles and equipment.... Get a oil pan heater pad. It will keep the oil warm and the heat will rise and warm the engine for quick startups. The oil will flow like a warm summer's day. And it consumes less electricity and does a better job than a block heater.

On a side note. There is a 10w40 diesel oil. Amsoil has one. It is listed in the auto oil section and not also in the diesel oil section (?). It is...

http://www.amsoil.com/storefront/amo.aspx

The "w" in a 5w40, 10w40, or 15w40 is the winter flow rate. They are ALL 40 weight oils. the 40 is not the "hot number". (at least with synthetics... dino a different issue). Synthetics will be a real 40 weight, whereas, a lot of conventional oils must use viscosity improvers to get the 40 weight. I guess you could arguably call that a hot number then. This is why Castrol advertises their Tection Extra version of diesel oil as having "continuously reforming molecules". At least that is what they advertise on my XM radio.

I'll settle for uniform molecules and not "continuously reforming molecules". My preference. Not going to down anyone who thinks different.


Oh... as for using a 15w40 in winter? I have used nothing but a 15w40 in my truck engines for the last 25 years (both conventional and synthetic). Including 6 full years in Alaska with temps down to -70F actual. Once the engine is at full operating temp, the oil is also. The only issue is at startup, and the heater pad takes care of that. Problem solved.

 

[dnewton3]

I just changed to 10w30 HDEO (Rotella) from the Rotella T Synthetic 5w40. I only run 4k-5k miles a year in my Dmax. Can't justify the expense of the "synthetic" for such a short OCI.

Risks/Rewards:
I'll run the 10w30 Rotella year round, even pulling travel trailer this summer. The only risks I see is the possible (though yet to be confirmed) evaporation of the slightly "thinner" oil, or a loss of "protection" due to thinner oil? I think that these risks are overblown most of the time, and I'm willing to be the test case ( because I'm that confident of the products). The reward(s) might be easier starting in winter, and/or slightly better fuel economy. I doubt I'll even notice such gains, but they might be there ...

Overall, if for nothing but an experiment to help shatter the myths, I'm doing it. Got the 10w30 on sale for $8.99/gallon.

Felt good about that decision, until Mobil brought the $3 rebate out, and now I can get Delvac for $7/gallon (but only in stocked stuff, which tends to be the 15w40). I don't "need" more oil in the garage, but I'm such a lubricant-junkie I'll probably head down Friday before the rebate ends. If only the 10w30 Delvac was available for the rebate, I'd be in heaven ...

 

[Bambam]

It doesn't get that cold here,maybe 0° and usually not for more than a day or 2. I do travel to Maine and upstate NY in the winter time where cold temps come and stay for a while. I am sure running 15w40 conventional would be just fine but I need to satisfy that part of my brain that talks to me when temps get cold and say,"John,oh Johnny boy,it's quite cold,hows that conventional oil going to do? Did you hear that,that scream of metal on metal,that wear,that abuse??"" AAAHHHH

Trying to live with the fear!

 

[addyguy]

Petro-Canada makes a 10W-40 diesel oil, if you really want that grade. Don't know if you can get it where you are....

 

[D-Roc]

Petro-Canada makes a 10W-40 diesel oil, if you really want that grade. Don't know if you can get it where you are.... [/quote
It is supposed to be quite good, as well..

 

[D-Roc]

Originally Posted By: D-Roc
Petro-Canada makes a 10W-40 diesel oil, if you really want that grade. Don't know if you can get it where you are.... [/quote
It is supposed to be quite good, as well..


aww Man, it's still all mucked up...sopme days I can't do anything right.

 

[dnewton3]

Hang in there D-Roc, it's almost the weekend!

 

[D-Roc]

Originally Posted By: dnewton3
Hang in there D-Roc, it's almost the weekend!


With the course I am on right now, My Friend, I need all the weekends I can get...

 

[JHZR2]

Originally Posted By: Arkapigdiesel
The film strength of a 30W is usually more than sufficient at operating temp. I would recommend a 40W year round if you tow heavy loads.

Check out my used oil analysis in the diesel section while running 10w30 Rotella.....wear looks very good.


Chevron technical folks (the people writing the SAE papers and doing the real analysis work) stated to me that a 10w30 is OK for a light duty diesel, i.e. pickups, but that there are still considerations to worry about. OE fills in european HD trucks can be 5w30 PAO based oil, but for now, 15w40 and 5w-40 are important.

So the flow characteristics of a 10w instead of a 15w- give benefit. 30wts are the future, even for diesels, so there isnt much to worry unless youre truly a HD user...

All the same, Id be inclined to go 5w-40 year round...

 

[D-Roc]

Originally Posted By: JHZR2
Originally Posted By: Arkapigdiesel
The film strength of a 30W is usually more than sufficient at operating temp. I would recommend a 40W year round if you tow heavy loads.

Check out my used oil analysis in the diesel section while running 10w30 Rotella.....wear looks very good.


Chevron technical folks (the people writing the SAE papers and doing the real analysis work) stated to me that a 10w30 is OK for a light duty diesel, i.e. pickups, but that there are still considerations to worry about. OE fills in european HD trucks can be 5w30 PAO based oil, but for now, 15w40 and 5w-40 are important.

So the flow characteristics of a 10w instead of a 15w- give benefit. 30wts are the future, even for diesels, so there isnt much to worry unless youre truly a HD user...

All the same, Id be inclined to go 5w-40 year round...



Good points...I feel the same way.