John Deere 318 HDEO 15W 40 Diesel Oil

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Thanks for both responses. Now, I'll try to figure out which 15W 40 full synthetic has the best shear resistance. I'm still a little curious about 20W 40 oils, since that multi viscosity is given in the manual. The only ones I've found are for motorcycles, and higher priced, except less so for the Supertech. I'm developing a new habit of more time than usual checking out oil in stores that carry it. My local TSC has a nice broad inventory (even a Traveller 30W HD with still an SG rating). Got to get to the closest Rural King to check out their oils.
You are over thinking this, especially with a unit with that may hours on it yet no oil consumption issues. Personally I have started using RT6 15w-40 but you have other choices.
 
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A 40-grade oil is always a 40-grade oil. The 15W-40 thickens somewhat less than a monograde 40 oil when cold to achieve the multi-grade winter rating. Winter ratings would be better described without numbers to prevent this misunderstanding.

Again no oil thickens as it warms up. Every oil thins as the temperature increases.
That's not entirely accurate. A 5w-40 has a minimum HTHS of 3.5 vs 3.7 for a 15w-40. HTHS viscosity is what matters for air cooled engines running in hot environments. I have one machine that experienced minor oil consumption with an oil having 3.1 HTHS. That went away with another oil having 3.5 HTHS. That same machine with a Briggs Intek V-Twin now has 15w-40 RT6 in the sump with no measurable oil consumption after 30 hours so far this season.
 
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Do you guys think that the HDEO oils with the higher zinc/phosphorous are better for OPE vs. the Diesel/Gas rated HDEO's (DELO) with lower zinc/phosphorous? Are there other undetected additives in these dual rated oils to make up for the lower zinc/phophorous?

Example of dual rated HDEO: https://www.chevronlubricants.com/en_us/home/products/delo-400-xle-sae-15w-40.html

Thanks
It's not undetected, Delo 400 SDE has a boat load of boron in it.
 

SwedeFP

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You are over thinking this, especially with a unit with that may hours on it yet no oil consumption issues. Personally I have started using RT6 15w-40 but you have other choices.
I know, and I tend to do that. Just like to make good decisions on things that could save me bigger money in the long run. I'm told this engine can cost up to $1500 to rebuild. I'm strongly leaning toward RT6 15W 40. It's pretty available locally.
 
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I have a 318 with a p218g engine. Straight 30 gives me the least consumption. 10w40 conventional isnt to bad. About the same as 20w50. For the last several years I have changed the oils in the fall with whatever synthetic I have laying around since I use it in the winter. 0w40 5w30 10w30 all have higher consumption in the summer but I top it off with whatever is laying around.

The most important thing that kills these Onan engines is low oil. Always keep it topped off.
 
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Well, I'm posting my first one here. I've got this mower with an 1985 Onan B43G engine. I've owned this 9 years (about 1400 hours on it), and always used 30W only in It-usually JD Torq Guard or Pennzoil. After getting more interested in researching oils for my F150 4.6L and Jeep Wrangler 4.0 here in BITOG, I am wanting to switch to 15W 40 which is spec'd in the owners manual (also specs 20W 40 but not too available). I've read a lot of threads on this type of oil, and can mostly only find ones like Supertech, Rotella, Delo, Delvac, etc., but most are diesel only rated. I read that Rotella dropped their gas ratting some years ago, so maybe it could be the exception and really still be fine for gas. I'd really like to go with a full synthetic for better engine heat management which I've read about on BITOG. I've got the usual John Deere 318 cooling issues covered with the grommet around the oil filter replaced, and a new firewall insulation kit coming. I'd also like to use the most shear resistant applicable oil. Am I safe to use this type of HDEO without having a gas rating? I'm just trying to hedge against my lack of knowledge of oil, thinking there may be something I'm not considering. I put around less than 50 hours per year on this mower in Tennessee, so a bit hot during summer. Right now, I don't use it in the winter, but am looking for a snow blade for winter. Oil and filter (JD or Wix) changed at the end of each sumner season.

15W40 HDEO will be my oil fill next season in my JD LT 150...

That being said since I solved my oil leak and cleaned the engine of debris the current fill of Super Tech FS HM 10W30 is holding up well.

Just my $0.02
 
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You could always try straight 40 weight oil, Chevron Delo 400 is great stuff, I believe it's actually use really high quality group II base oils, so even though it's not full synthetic it's still very good oil, super high in the anti wear additive department, compared to the straight 40 that was available at the time the manual would've been written this more modern straight 40 made with high quality group ii base oils should be closer to 25W40 whereas that old solvent refined stuff that would've been around when the manual was published was more like gel at anywhere around freezing.
I found some of the Delo aparently on close out from some trucking supply company, you'll want to try to get free shipping, you can't just buy all Delo because after 6 jugs it tells you that freight shipping is the only option, but I found a case of Rotella T5 10W30 that puts the order over $50 and still get free shipping, also use the promo code "RETAILMENOT10" in the checkout to take off 10%
Delo 400 SAE40 Gallons: https://www.finditparts.com/products/8609692/chevron-235120339
Rotella T5 10W30 3x1gal: https://www.finditparts.com/products/11513488/shell-lubricants-550045130
You can also play around and try to find other items that may work to keep you at $50 and still get free shipping. Amazon has gallons of this oil but They're like $30 each which is too much to pay for 1 gallon of straight 40.
 

SwedeFP

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You could always try straight 40 weight oil, Chevron Delo 400 is great stuff, I believe it's actually use really high quality group II base oils, so even though it's not full synthetic it's still very good oil, super high in the anti wear additive department, compared to the straight 40 that was available at the time the manual would've been written this more modern straight 40 made with high quality group ii base oils should be closer to 25W40 whereas that old solvent refined stuff that would've been around when the manual was published was more like gel at anywhere around freezing.
I found some of the Delo aparently on close out from some trucking supply company, you'll want to try to get free shipping, you can't just buy all Delo because after 6 jugs it tells you that freight shipping is the only option, but I found a case of Rotella T5 10W30 that puts the order over $50 and still get free shipping, also use the promo code "RETAILMENOT10" in the checkout to take off 10%
Delo 400 SAE40 Gallons: https://www.finditparts.com/products/8609692/chevron-235120339
Rotella T5 10W30 3x1gal: https://www.finditparts.com/products/11513488/shell-lubricants-550045130
You can also play around and try to find other items that may work to keep you at $50 and still get free shipping. Amazon has gallons of this oil but They're like $30 each which is too much to pay for 1 gallon of straight 40.
I thought about trying 40, since right now, the mower is only used in the summer. There is the temp restriction from the manual to hinder that. If I went with a 40, Delo would be one to consider. Thanks for the links.
 
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Thanks for posting that information about these old engines. I end up adding maybe an ounce or two between mowings. I've recently looked at that gasket type part that goes around the oil filter to seal off the air that could come out of the engine compartment instead of going mature toward cooling the right cylinder, and saw no leaks. I keep a piece of cardboard under it, and see no oil spots.
I kind of baby this mower, as after mowing I use a leaf blower on the deck top, through the air grates on the side plates and around the battery, then through the front grill then the top of the engine. I've never had a grass build up yet. I keep the belly screen on, and clean it. Heck. I even park it in a cool basement, and then open the hood and put a fan on high at the front grill and blow air over the cylinders. Now, I'll add to that the HDEO 15W 40. My insulation is shot, but have a new kit coming from John Lang who makes them in three pieces so no engine removal is required.
You're welcome! Glad to see another awesome Deere doing some work! I have an '84 316, originally had a B43E Onan, but that had some pretty bad rod knock. I ended up doing an engine swap/re-power with an 18HP Vanguard V-Twin. I use 15W-40 Traveller or Rotella in the Summer and 5W-40 Delo or Rotella T6 in the winter months. I run Wix 57035 on the Vanguard.

I have my Vanguard out of my 316 at the moment (I was adding the OEM oil cooler but now found out it doesn't fit. I am also replacing my insulation and just cleaning the thing up. Next steps over here will be re-assembly, some touchup painting and getting ready for winter. I have had a lot of good luck with Fluid Film/Woolwax as undercoating to literally stop any rust from happening at all.
 

SwedeFP

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You're welcome! Glad to see another awesome Deere doing some work! I have an '84 316, originally had a B43E Onan, but that had some pretty bad rod knock. I ended up doing an engine swap/re-power with an 18HP Vanguard V-Twin. I use 15W-40 Traveller or Rotella in the Summer and 5W-40 Delo or Rotella T6 in the winter months. I run Wix 57035 on the Vanguard.

I have my Vanguard out of my 316 at the moment (I was adding the OEM oil cooler but now found out it doesn't fit. I am also replacing my insulation and just cleaning the thing up. Next steps over here will be re-assembly, some touchup painting and getting ready for winter. I have had a lot of good luck with Fluid Film/Woolwax as undercoating to literally stop any rust from happening at all.
Glad to see you re-powered, since these are such stout garden tractors. When the time comes, I'll have to look at all the options. I just bought some 15W 40 Mobil Delvac Extreme synthetic (read a long thread on bitiog about whether it was really synthetic) for mine. Price was a factor with $2 less than RT6, and a $9 rebate, so about $11 per gallon. I learned about Fluid Film from a Jeep forum and have a couple of cans, but hadn't thought of it on the 318- thanks, that's a great application. Think I'll get more and go over it and the bottom of the deck this winter.
 
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@ SwedeFP

This guy does a good job describing the multi grade viscosity concept in engine oils quite well:


The main thing is that as oil heats up, its viscosity decreases, i.e. the oil flows better as the oil gets warmer.
 
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However flow is largely irrelevant in an ICE as long as the oil can be pumped. Having it run down little ramps makes for good videos but that’s not representative of engine operation.
 
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I have a 318 with a p218g engine. Straight 30 gives me the least consumption. 10w40 conventional isnt to bad. About the same as 20w50. For the last several years I have changed the oils in the fall with whatever synthetic I have laying around since I use it in the winter. 0w40 5w30 10w30 all have higher consumption in the summer but I top it off with whatever is laying around.

The most important thing that kills these Onan engines is low oil. Always keep it topped off.
This.

They will live forever, just keep the oil full and the cooling screens/fins clean. I believe the 300 series Deeres pull air from below the tractor, make sure that area isn't plugged with grass and debris.
 
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