Diesel Oil Fans Information

[lynnmor 7,556]

I know that this video mentions direct injection quite a bit, but the basics should pertain to any type of diesel or gas engine.

Edited April 6 by lynnmor

[HyperPete 475]

Pretty awesome.  Ive been using Rotella in all of my motorcycles for decades.  Time to rethink this.

Thanks for the video!

[squonk 42,503]

I'm sticking with Rotella. Read the comments. Many folks have been using it for years like myself with great results. Direct injection engines are junk. Many fail with the "proper oil " When Honda and Toyota are having problems it's not the oil.

Edited April 6 by squonk

[adsm08 2,633]

2 hours ago, squonk said:

I'm sticking with Rotella. Read the comments. Many folks have been using it for years like myself with great results. Direct injection engines are junk. Many fail with the "proper oil " When Honda and Toyota are having problems it's not the oil.

 

The problem isn't direct injection, it's quality control and cost-cutting.

 

We have jacked the price of vehicles so high with fancy features like touch-screens, navigation systems, blind-spot/ADAS/Driver unawarness aides, etc that instead of ditching the BS they have slashed QC on the powertrains. Tolerances are too loose, and it causes issues like oil consumption.

 

Earlier DI engines that were built prior to those other events are fine. Look at how often the 2.0 Focus from 13-18 had actual engine issues.

[1991Bills 520H 1]

Thanks for the video, lots of interesting info there. I follow Lake Speed, Jr.’s Oil Geek channel all the time, but I must have missed this video. I’ve seen on other small engine chat rooms many users of the Shell Rotella diesel oil products in small gasoline engines without having any issues over many years of use and I’ve recently wondered about using Rotella T6, for example, myself. I started with running 30 W oil  (per the owners manual) in my 520H  for about the first 15 years (it only gets used in the summer in upstate NY). I then started using a full synthetic ever since, usually Castrol Syntec or Mobil 1. I haven’t had any oil consumption issues and engine continues to run well. When my 520H was mfg'd, full synthetic oils weren’t commonly used in small equipment which would be why TORO didn’t spec it in my manual back then. I’ve wondered what Toro or Onan (now Cummins) would currently specify if they were to update manuals (not likely for out of production equipment). Does anyone here know if there’s any newer manufacturer oil specs for Onan engines?

[Bill D 2,086]

22 hours ago, 1991Bills 520H said:

Thanks for the video, lots of interesting info there. I follow Lake Speed, Jr.’s Oil Geek channel all the time, but I must have missed this video. I’ve seen on other small engine chat rooms many users of the Shell Rotella diesel oil products in small gasoline engines without having any issues over many years of use and I’ve recently wondered about using Rotella T6, for example, myself. I started with running 30 W oil  (per the owners manual) in my 520H  for about the first 15 years (it only gets used in the summer in upstate NY). I then started using a full synthetic ever since, usually Castrol Syntec or Mobil 1. I haven’t had any oil consumption issues and engine continues to run well. When my 520H was mfg'd, full synthetic oils weren’t commonly used in small equipment which would be why TORO didn’t spec it in my manual back then. I’ve wondered what Toro or Onan (now Cummins) would currently specify if they were to update manuals (not likely for out of production equipment). Does anyone here know if there’s any newer manufacturer oil specs for Onan engines?

I run Mobil 1 10W-30 in all my equipment.  No issues so far.  I can get it at BJ'S for $32 plus tax for 6 quarts.  Best price I've found.

[HyperPete 475]

7 hours ago, Bill D said:

I run Mobil 1 10W-30 in all my equipment.  No issues so far.  I can get it at BJ'S for $32 plus tax for 6 quarts.  Best price I've found.

 

You need to visit the jungle:

 

https://a.co/d/7sKZ7It

[johnnymag3 2,559]

Rotella 30w...............Amazon   Buy the case !!!!

[8ntruck 7,375]

Interesting.  But, mostly aimed at current diesel and gas automotive/truck engines, not old small engines.

 

I'm going to guess that our old small engines operate at lower stress levels and don't get as many operating hours as the current automotive/truck engines referred to in the video, so they won't be as sensitive to the additive package in whatever oil is used. 

 

I'm still of the opinion that the current automotive oils are optimized for roller cams and the current journal bearing materials and coatings - which is not what is inside of our Kohlers and Onans.  I'll opt for the added zinc in the oil for my horses.

[Fordiesel69 267]

So in a small engine that is a throw away design, like the briggs intek, kohler courage / residential commands, honda GVC series, and etc I would be any oil changed often will be just fine.  However when we step up to a vintage engine with all metal parts such as the kohler K series / magnum, onan, briggs i/c, and vangards where they can last 2 or 3 rebuilds, this is where the diesel oils will protect the cams.  

 

Kohler K series / magnums shred a lot of iron.  That is why you need a 25 hr max interval.  It doesn't matter if you use some space age synthetic formula the iron is still contaminating the oil and grinding down the rest of the engine.  On vintage engines it is best to use a good diesel oil to protect the cam and tappets.  Also the big end connecting rod is just aluminum, there is no bearing to protect the crank pin.  Bad / contaminated oil will severly damage the conecting rod and crank pin.  

[squonk 42,503]

Good ol' Rotella 30W used in an old 67 K181 for the past 5 years or so. Enough said. 

 

[HyperPete 475]

On 4/17/2025 at 10:27 AM, Fordiesel69 said:

So in a small engine that is a throw away design, like the briggs intek, kohler courage / residential commands, honda GVC series, and etc I would be any oil changed often will be just fine.  However when we step up to a vintage engine with all metal parts such as the kohler K series / magnum, onan, briggs i/c, and vangards where they can last 2 or 3 rebuilds, this is where the diesel oils will protect the cams.  

 

Kohler K series / magnums shred a lot of iron.  That is why you need a 25 hr max interval.  It doesn't matter if you use some space age synthetic formula the iron is still contaminating the oil and grinding down the rest of the engine.  On vintage engines it is best to use a good diesel oil to protect the cam and tappets.  Also the big end connecting rod is just aluminum, there is no bearing to protect the crank pin.  Bad / contaminated oil will severly damage the conecting rod and crank pin.  

 

My takeaway from the video is that higher zddp (zinc) levels in diesel oil are negated by the soot-fighting additives to diesel oil, so that far lower values in automotive oil actually provides for more available zinc.

I have used Rotella T5 & T6 in my small engines & motorcycles for decades, but now I'm considering switching back to automotive oil.

Ultimately, I believe that any modern motor oil will be fine when changed regularly, but I have got to have "the best"!

[stvski80085 139]

I use the kohler oil.  It has extra zinc.  Since it’s a quart I don’t mind paying a little more for it.