oil grades
My new 2016 Ford Power Stroke F 250 diesel recommends oil 5w-40 syn. oil for towing. I’ve been using 15w-40 Shell Rotella. What oil have you been using?
Forum Discussion
Follow the OEM's recommendations (and if not...then the OEM has a position
to deny any warranty coverage), follow the herd, or learn about the
metrics of ICE oil properties vs your application (the OEM manual
has two or more different viscosity recommendations and is by usage
(terrain/ambient, duty cycle, etc)
The OEM employs many lube experts (many are PhD's and PE's), along
with working with lube provider experts/charts/documentation/etc
to derive their recommendations with-in the manual(s)
A constant learning topic for me and if you folks want to discuss
this in more detail...suggest (if not already on these or other tech
pages on the topic) reading up...or not and just follow the herd...
Good starting point and follow the sub-links
viscopedia starting page
What is Viscosity? Learn more about the flow behavior of liquids
Best page showing the relationship(s) affecting and subsequent effects to viscosity
Factors Affecting Viscosity
Several other attributes to ICE oil, but shear strength is the main one...IMHO
Temp & duty cycle are close seconds...as they affect shear strength
directly
to deny any warranty coverage), follow the herd, or learn about the
metrics of ICE oil properties vs your application (the OEM manual
has two or more different viscosity recommendations and is by usage
(terrain/ambient, duty cycle, etc)
The OEM employs many lube experts (many are PhD's and PE's), along
with working with lube provider experts/charts/documentation/etc
to derive their recommendations with-in the manual(s)
A constant learning topic for me and if you folks want to discuss
this in more detail...suggest (if not already on these or other tech
pages on the topic) reading up...or not and just follow the herd...
Good starting point and follow the sub-links
viscopedia starting page
What is Viscosity? Learn more about the flow behavior of liquids
Best page showing the relationship(s) affecting and subsequent effects to viscosity
Factors Affecting Viscosity
Several other attributes to ICE oil, but shear strength is the main one...IMHO
Temp & duty cycle are close seconds...as they affect shear strength
directly
viscopedia wrote:
Shear Rate
The shear rate is an important parameter in defining viscosity (refer to the two-plates model) and also in specifying a substance's flow behavior.
The vital question is whether a change of shear rate does or does not change a fluid's viscosity. This question draws the line between Newtonian and non-Newtonian fluids.
Ideally viscous or Newtonian Liquids
If a fluid's internal flow resistance is independent of the external force – i.e. the shear rate - acting upon the fluid, it is ideally viscous. Such fluids are named Newtonian liquids after Sir Isaac Newton, who discovered the mathematical relation between viscosity and the external force acting upon a fluid. A viscosity function means plotting the viscosity over the shear rate. The viscosity function of a Newtonian liquid is a straight line (curve 1). Typical Newtonian liquids are water or salad oil.
Non-Newtonian Liquids
If a substance is not ideally viscous, its viscosity changes with the shear rate. For such substances the apparent viscosity is specified. There are substances that show shear-thinning behavior (curve 2). Their viscosity decreases when the shear rate increases. For other substances the viscosity increases with increasing shear rate – that is called shear-thickening (curve 3).
For example yoghurt and shower gel show shear-thinning behavior, while starch solutions show shear-thickening behavior. These are just two of the most basic examples of potential flow behavior. Learn more about how shear rate can influence a substance’s flow behavior in World of rheology.
