I am due for a oil change and would like to switch to Rotella 5w-40 because the winter is on its way but is it too soon? We don't go below 40 at night. I only put about 4k on my truck a year so a change now will get me well through the winter.

 

Why not!
Iam a rocks throw from you somewhere on LI!
I run 5w30 syn all year round.
The 5w is your cold flow weight.

Bill

 

Manufactures recommend thiner oil in winter only. Thought the thiner oil in warmer whether might be a bad thing. How many miles do you go on the syn before a change?

I went 4000 on dino and Blackstone said I had plenty of additive left. Had 5.1 1 would be low.

 

my '97 has 187,000 miles on it running ROTELLA 5W/30 Synthetic, the truck has been in Arizona since '99 and about 6 years in the Phoenix area, 120 degree days and never had a problem, so no I don't think it is too warm in New York to run 5W/30

 

How about the 5w40? Is the 40 to much?

 

with multi weight oil the first number is cols flow characteristics and the second number is hot characteristics so having said that 5W/40 will be as thick as 5 weight when cold and at operating temp the 40 will be as thin as strait 40

 

I never understood why you wanted it thicker when cold and thinner when warm.
Seems you'd want thinner when cold and thicker when warm.
Ahh who knows.

Anyways.

Blackstone never sent me my test kits. I'm kinda bummed out bout that.

 

A thin oil has a lower number and flows more easily, while thick oils have a higher number and are more resistant to flow.

So its opposite of that...

Oil is one of those things that is very commonly misunderstood... I have reaseached oil in depth for a school project once, I know more about engine oil than most...

 

Multi-grade motor oil

The temperature range the oil is exposed to in most vehicles can be wide, ranging from cold ambient temperatures in the winter before the vehicle is started up to hot operating temperatures when the vehicle is fully warmed up in hot summer weather. The difference in viscosities for any single-grade oil is too large between the extremes of temperature. To bring the difference in viscosities closer together, special polymer additives called viscosity index improvers are added to the oil. These additives make the oil a multi-grade motor oil. The viscosity of a multi-grade oil still varies logarithmically with temperature, but the slope representing the change is lessened. This slope representing the change with temperature depends on the nature and amount of the additives to the base oil. To compare the variation of viscosity on temperature in a multi-grade oil with single-grade oils, two reference points are used. One is at cold (Winter) temperature, 0°C (32°F), and the other is at the hot operating temperature, 100°C (212°F).

Accordingly, the SAE designation for multi-grade oils includes two grade numbers; for example, 10W-30 is the designation for a common multi-grade oil. The first number associated with the W, the 10, means that the viscosity of this multi-grade oil at winter temperature corresponds to the viscosity of a single-grade 10W oil at winter temperature. The second number, 30, means that the viscosity of this multi-grade oil at hot operating temperature corresponds to the viscosity of a single-grade 30 oil at the operating temperature. The controlling SAE standard is called SAE J300. The motor oil grade to be used in a given vehicle is specified by the manufacturer of the vehicle.

Engine oil - Definition of Engine oil by the WordIQ Dictionary, Encyclopedia and Thesaurus