Switching to 10W-30

reddogge

Member
I've run 30 weight in my 9N for the past 25 years but would like to switch to 10W-30 when I change oil to help it turn over in the winter better. Any ramifications in switching viscosity?
 
(quoted from post at 15:46:50 10/13/14) I've run 30 weight in my 9N for the past 25 years but would like to switch to 10W-30 when I change oil to help it turn over in the winter better. Any ramifications in switching viscosity?

Yes - improved cold cranking.

TOH
 
Regular conventional 10w-30 would be fine. Napa house brand or Walmart Super Tech are fine cheap options. Also, I would look at 15w-40 if you are a little low on the pressure. I like JD plus-50 II because it formulated for ag engines, but others use Walmart house brand Super Tech, Rotella T to good effect.

Run the engine red hot and change the oil before you put it up for the winter. Shouldn't have any issues changing from one viscosity to the other. I never have on these engines.
 
I use 15w40 in all my vehicles because they're all
older type that need ZDDP to keep the cams from
wearing quickly. The oil designed to use in modern
engines are not too good for these old relics. You
can get additives which contain ZDDP,and should be
OK if added. lha
 
I used shell rotella 15w40 diesel oil.
This oil still has the zinc additive that the old SCHOOL engines need.

EPA has required they take out zinc from regular car/truck non diesel oils.

however you can buy a zinc additive if you elect not to use a diesel oil.

I change the tractor, mower oils in the spring to get the watervapor and dirt out of the oil due to evaporation in the motor block.
 
i'd consider 15w40 if you are thinking of going to 10w30 from 30w.

many of the same benefits, but generally a better oil add package.
 
(quoted from post at 16:41:49 10/13/14) I used shell rotella 15w40 diesel oil.
This oil still has the zinc additive that the old SCHOOL engines need.

EPA has required they take out zinc from regular car/truck non diesel oils.

however you can buy a zinc additive if you elect not to use a diesel oil.

Use whatever you want but you are tilting at zinc windmills.

The current level of phosporous (the anti-wear element is not zinc - it is the phosphorus that comes with the zinc in the ZDDP additive) is more than adequate for the valve train on a 25HP low RPM flat tappet engine with 30# valve spring pressures. It is also a little higher than the levels you would have found in the vast majority of 1940-1960 engine oil formulations. The truth is [u:ec002cce81]most[/u:ec002cce81] "old school" flat tappet production engines are perfectly happy at 600-800 PPM phosporous.

And if you have a "high performance" engine that actually needs a higher level of phosphorous you don't have to go to diesel oils to get it. The SL/SM service class limits on zinc/phosphorous only apply to viscosity grades SAE xxW20 and xxW30. An SAE xxW40 grade SL or SM service class oil can have as much as 1400 PPM.

Anything much more than that and the zinc and phosphorous will start to chemically eat the metal away accelerating camshaft and tappet wear. So make sure you understand the chemistry and be mighty careful what you are adding to your oil.

TOH
 
You will be fine, might even want to go to 5W-30 in the winter if it sits out in the cold. I use 15W-40 Delvac year round in all my equipment, but it sits in heated building.
 
(quoted from post at 16:43:36 10/13/14) I just bought the 10W-30 Rotella from TSC. Should I switch it for 15W-30 or would I be good to go?

I'm assuming that is their Rotella T5 SAE 10W30 which is a semi-synthetic diesel/gasoline (CJ4/SM) rated HD engine oil with elevated levels of zinc/phosphorous (1200/1000 PPM). Like all diesel oils it also has a high detergency with calcium north of 2200 PPM. You are good on all fronts and even the Roger Ramjets with their high performance flat tappet engines should be happy with the ZDDP levels in that one :twisted:

TOH
 

I use the Rotella 15W-40 Diesel all year. The chemical composition keeps my 8N happy.
The oil weight keeps my oil pressure at 25-30 lbs even after running for a few hours. Anything thinner knocks my pressure down to about 15-30 lbs.
 
that looks like 10w40 would be the sl/sm choice vs a 15w40 s/c rated oil. not a whole lotta difference until you get a bit colder? almost looks like a hair split.

in my are 10w40 oil is actually more $ than 15w40 ( cheap brands for both )
 
(quoted from post at 14:03:54 10/14/14) that looks like 10w40 would be the sl/sm choice vs a 15w40 s/c rated oil. not a whole lotta difference until you get a bit colder? almost looks like a hair split.

in my are 10w40 oil is actually more $ than 15w40 ( cheap brands for both )

Maybe no difference in Florida but a significant difference in colder climates. This graph is Rotella T5 viscosities above freezing. The differences get exponentially greater below freezing - and I mean that quite literally.

TOH

Rotella_T5.jpg
 
wow.. 1000 / 1500 impressive.

the difference inthe 10/15 base must be huge when cold.

that's what we need. some cheap 5w40 :)

the 5w40 i put in my powerstrokes are anything but cheap. valv premium blue full syn... 16 qts per oil change. yum!
 
no you don't need to switch the 10WX30 for 15WX40. I have seen hundreds of those oil co graphs. They can make them say almost anything they want, to show an advantage to their oil over another brand.
 
(quoted from post at 17:19:29 10/14/14) no you don't need to switch the 10WX30 for 15WX40. I have seen hundreds of those oil co graphs. They can make them say almost anything they want, to show an advantage to their oil over another brand.

I am all on board with the 10W30 grade for an N-series which is why I posted the graph. A picture is worth a thousand words and it makes it clear that there is a very significant difference in the cold weather behavior of the different grades and very little difference when hot. The graph is all about the difference in grades and has nothing to do with any particular brand of oil. These examples just happen to be Shell Rotella in three different grades - you will see pretty much the same picture using any brand of oil in those grades. The graph is mine and there is zero oil company marketing involved in the charting.

I used the actual kinematic viscosities of the subject oils measured at 40C and 100C. You can get that from the technical data sheets for the oils or any independent virgin oil analysis (VOA) - plenty of them floating around the web..

The viscosity/temperature curves are computed from that data using [u:b616c9f68c][i:b616c9f68c]ASTM Method D341-09 - Standard Practice for Viscosity-Temperature Charts for Liquid Petroleum Products[/i:b616c9f68c].[/u:b616c9f68c] I cheat and use a little online calculator app that does all the math and plotting for me. Then I just cut and paste the screen shot. :roll:

What you will find in real life is going to be very close to what those engineering calculations show. If not you might want to bring it to the attention of the [u:b616c9f68c]ASTM[/u:b616c9f68c] ;-)

TOH
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top