Say Rotella T-1 SAE 30 ($18 gallon) vs Rotella T4 15W40 ($16 a gallon) to keep it brand comparable.
In something like a pressure washer or generator in hot weather.
In something like a pressure washer or generator in hot weather.
Straight 30 or 15W40 for hard use air cooled small engine?
- Thread starter z71bill
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FWIW, I'd use 15w40 or 5w40 (for easier starting) in any OPE over 30. Just easier to find IMO.
Just my $0.02
Just my $0.02
OTOH, the 30 is a straight weight with a lot of VIIs in it. I find in my OPE a straight weight holds up better, even if not as thick, because it is not as adulterated. If you need to run it in sub-freezing temps, then the multigrade makes sense. OTOH, what is the difference between T1 and T4? I’m not familiar with T1 and this sounds like it might not be an apples-to-apples comparison.
They aren't fussy. Long as there's oil and it's not the factory fill from 1984 it'll be fine.
(Did small engine repair in a shop for several years)
(Did small engine repair in a shop for several years)
Why would an SAE 30 contain "lots of VIIs in it"? It can be made with straight base stock and no VII. Rotella T1 SAE 30 has a VI of 101 (PDS). It likely contains base oil, DI package and maybe additional PPD.
Say what?
Whatever viscosity oil the manufacturer recommends I would run but in full synthetic and run it without worry. If 5w/30 is spec'd - running a 5w/30 full syn is better then running a higher viscosity 15w/40 - since breakdown is really not an issue and running the thicker oil will provide no real benefits and might actually cause a hotter running motor due to the heavier viscosity.
This is my experience as well… as long as they’re kept full of some sort of oil it’s fine… I use whatever I have on hand, be that 5w-30 or 15w-40
That was supposed to say “LOTS LESS” and the dang auto-correct took it out/clipped it and I missed it. My bad. I mainly use an iPad and the native auto-correct changes a lot of words. I have to proofread like it’s Middle School; overall does NOT reduce errors and creates more issues.
Sorry.
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I have 6 rental generators all Generac GP6500 and 6500E and the 15w40 Lucas or Mystyk that we use in powerstrokes gets used in these also
The typical hours on each oil change is about 90 to 100 hours
Thousands of hours in total no issues
The typical hours on each oil change is about 90 to 100 hours
Thousands of hours in total no issues
Either will be fine. What is important is that the oil is changed on a regular basis.
15w40 HDEO is the new SAE 30 in my opinion.
And per SAE J300 I don't think a properly labeled monograde can contain any VM, not just a lot less. The reverse is true that you can have a multi-viscosity oil with no VM but not the other way around.
The HTHS requirements for a 5w-40 differ from a 15w-40. I would be less inclined to run a 5w-40 in Houston.
In this case it does matter. See SAE J300. HTHS of 2.9 vs 3.7 matters a lot in high temperature / high load applications. Just ask CUJET about all the rod failures on generators running 5w-30 after hurricanes in Florida. 5w-40 is just a 5w-30 on mild steroids; it's not anything close to a straight SAE30.
I run 20w50 in my small gas stuff, but I do run it into moderately cold weather
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