Schaeffers 5w-40 or 15w-40?

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Hello, I drive a 2007 Duramax and currently run the 7000 series 15w-40 with the #132 EP Moly Additive. For the difference in price, would switching over to the 9000 series 5w-40 be better? The truck is bone stock and currently has 53K miles on it and tows an 8K trailer every day throughout the summmer months and plows snow in the winter. I currently run approx. 10K OCI's and run the Mobil 1 M1-303 oil filter. The cost really isn't an issue, just want to keep the turbo and engine as clean as possible.
 
Definitely run the 5W-40 in the winter there for better flow during cold starts. To keep it simple, I would just run the same 5W-40 all year for only about $3-4 more per gallon than the 15W-40.

If you were in FL, TX, or AZ, then I would say you could just stay with the 15W-40 all year and be fine.
 
I don't see any issues with the Schaeffer's 15W40. It has similar cold temp characteristics as Amsoil AME 15W40 which is what I currently run. I have lots of times when it's pushing -20C and not plugged in, and I'm fine.
Not sure if it gets as cold where you are as it does where I live...I really don't think so.
 
I really like the Schaeffer's 7000 series 15W-40, but either would be fine. Neither of those two oils need the #132 added to them. They already have all the moly you could possibly need. Personally if it was my Duramax, I would use the 15W-40.
 
we switched our'06 dmax out from 15/40 to 5/40 RTS and it starts better, sounds better wile warming up shows more rpms wile warming up vs the 15/40,just all around better truck with the 5/40.

in cold weather 5/40 all the waaay!
 
Originally Posted By: Johnny
What? The "Always"..Mobil 1 guy put RTS in his Duramax.

One of our work trucks not mine or i'd have TDT in the pan.
grin2.gif
 
Hmmmmm....
I smell something....did da man slip and casually admit to being a closet Rotella user...or is he straight with us?
lol.gif
 
Originally Posted By: Steve S
The oil won't make a difference if you shut the engine off when the turbo is hot.

dmaxs have auto shut down,turbo needs to cool before computer shuts engine off.
 
I just wanted to change the title of this thread back to what it originally was.

I do like the safety factor for the shut down. Does Ford and Dodge to this?
 
To answer your question about how cold it gets here. It typically gets down to 15F or so with occasional dips below 0F and extremes down to -33F as recorded at our shop last winter. I guess my question pertained to the content of the PAO in the 5w-40. Does the 15w-40 have the same basic composition as the 5w-40 or is it a different blend all together?
 
I believe both have 20-25% PAO. The 15w40 has grp II/PAO, while the 5w40 has grp III/PAO. I'm pretty sure on this but someone correct me if i'm wrong.

FYI, the TDS' list the 5w40 at
I agree with others as well, the Moly treatment isn't necessary. If you prefer to use it though, it won't hurt anything. Just as Johnny said, the oil already has plenty of Moly.
 
I thought 132 did not actually have much moly - in that it had a lot of antimony and that was the big value add. Assuming this is true - there may be value in continuing to add.
 
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Originally Posted By: Jax_RX8
I thought 132 did not actually have much moly - in that it had a lot of antimony and that was the big value add. Assuming this is true - there may be value in continuing to add.


True, I think as the story goes they mention Moly because it was a better name for the product, but it contains little or no Moly IIRC. We used it this past summer in my brothers boat and were happy with it. Maybe Salesrep can weigh in on this.
 
I am familiar with the benefits of Moly. But I don't know what the Antimony does. Maybe someone can explain that to me. So, if I understand this correctly. The 5w-40 has a higher grade base oil than the 15w-40 but contains roughly the same PAO content. Over the course of the life of the truck/engine, will it actually make any difference? The cold flow characteristics seem to be similar, yet the 15w-40 doesn't have nearly as many Viscosity Improvers. Here where I live, it doesn't get that hot during the summer. Average highs are in the low to mid-80's with extremes reaching well into the 90's and occasionally 100's.
Of course any fuel mileage increase would be a plus as I do drive a lot of highway miles during the summer months. I do remember reading somewhere on this site that the 15w-40 actually flows like a 7-8w-40. Has anyone else seen this on a VOA or UOA?
 
Originally Posted By: daman
Originally Posted By: Steve S
The oil won't make a difference if you shut the engine off when the turbo is hot.

dmaxs have auto shut down,turbo needs to cool before computer shuts engine off.


Unless they have some new feature I'm not aware of, this isn't ture. I know FOR SURE my Dmax doesn't have it. I don't think any of them do. The OP stated his truck was pure stock, so I doubt he has that either.


Further, central OH isn't any different than central IN, where I'm at, weather wise. There is no "need" for a 5w-40 synthetic in this area. It's nice to have as an option, but it's not needed. GM recommneds 15w-40 dino oil down to zero deg F. They also approve 10w-30 at those temps. I've run both, and I must admit that the 10w-30 starts easier and builds pressure a bit quicker. In this area, I don't see a "need" for 5w-40 synthetic. Nothing wrong with using it if you choose, but don't try to convince yourself or others that it's needed. Dino 10w-30 is very well suited to this area, and year round use; I've got a UOA to prove it!
 
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like stated above 10w-30 is sufficiant, i'm in nw ohio, so basically same weather conditions.

as i have stated in many other debates on this topic, 10w-30 can be purchased for just about half the price of 5w-40, i'm running it in my 07 powerstroke this winter after sub-par uoa's on rts 5w-40.


schaffers has a very good reputation, i have friends running it in trucks and heavy equipment with very good results, the only thing that bothers me is over in the uoa section there has been several elevated lead #'s with the 5w-40 schafers
 
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