I have no evidence but have recently heard that oil has shelf life. Some say shake well before use and some say don't put it in engine period. Stay tuned, maybe someone with information will chime in.
15W40 or 5W40
- Thread starter kcs 61
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My read is that 5w-40 does everything 15w-40 does and then some. So there's no downside to running 5w-40 other than it probably costs more. You don't need it if it's not super cold, but it'll probably be a bit better on reducing wear on startup (which is when most wear occurs). But as @number two has said, for most of us we'll never wear out a Kubota engine, that needs minimum 4,000 hours. If you use it 10 hours a week, then that's 400 weeks =7.671 years. (My browser just auto completed that, which was weird). If you use it 5 hours a week that's 15 years.
If you're making a living with your machine and running it 40-60 hours a week, then it might matter.
If you're making a living with your machine and running it 40-60 hours a week, then it might matter.
In the interest of technical accuracy - almost but not quite.
Two downsides often discussed in diesel forums is time in grade and a potentially lower High Temperature High Shear (HTHS) viscosity.
Multigrade engine oils with larger viscosity spreads tend to have higher cincentrations of VI improving additives and are more susceptible to permanent viscosity loss due to shear. That means they will "wear out" and drop below the minimum viiscosity of grade 40 quicker.
HTHS is a similae issue for similar reasons. Oils with higher cincentrations of VI addituves are more susceptible to temporary viscosity loss under HTHS conditions.
Consequently the minimum requirement set by SAE J300 is 3.5 cP for grades 0W40, 5W40, and 10W40.
The minimum for grades 15W40, 20W40, 25W40, and 40 is slightly higher at 3.7 cP
That is why for decades 15W40 was the defacto standard for heavy duty diesel engine oil.
Now let me put that in perspective. Kubota recommendations include SAE grade 10W30 which has a minimum HTHS of 2.9 cP and grade 20 which has no minimum at all.
Dan
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GreensvilleJay
Well-known member
Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
THAT is be the line GM uses for THEIR engine failures being recalled though.......
GreensvilleJay
Well-known member
Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
I've got lots of CDN quarts of SHELL 10W40 from the late '70s, an dyes I shake it well before using. That gets the additives 'redistributed' before being poured into whatever engine needs it.
Sweet tea ….. STILL tastes sweet. That’s all that’s necessary for the average cafe-customer….who couldn’t care less if it were sweetened with white granulated sugar …or any one of many similar-tasting sweeteners or corn-derived fructose.
5W40 oil behaves like low VISCOSITY oil when it’s cold…and behaves like high VISCOSITY oil when it’s hot….which is all normal people need or want to know.
(However, it’s well-accepted that NONE of us here at OTT are ”normal”.)
I thought Yours were shot-off in Viet Nam….I guess my taste buds are more discriminating than yours.
Dan
I think you are confused. I have never been anywher close to anyplace in SE AsiaI thought Yours were shot-off in Viet Nam….