Real World difference between a 0W and 5W oil

[dsmith41]

I have been running a 0w30 (group IV, if it matters) oil for a while but I want to switch to a 5W-40 (group III, if it matters) oil soon just because it is much cheaper and still a great oil. But I am wondering if there will be much difference between these two oils in the dead of winter. Where I live, temps can drop to between -10 and 0 easily. It's not arctic by any means but still cold.

I know there is a difference between the two oils in the lab but I don't drive my pickup in a lab. Will it make a difference in my driveway?

 

[tomcat27]

I wouldn't hesitate to use the 5w-40 in warmer weather; but I would be more confortable using the 0w30 from Decvember thru March in this part of the country - especially without a garage. of course, you dont mention the car, miles, etc. is it a beater? basic transportation? your baby? certainly many engines live a very long life on 5W-X oils. actually, for the mainstream, that's all we had until recently. and when I was in college everyone used 10w30 or 10W-40.

 

[ZZman]

A zero weight oil would have better base oils. In cold weather it would flow quicker so you should see less strain on the motor, less filter bypass, less noise at cold start up, quicker turn over.

 

[ARCOgraphite]

Originally Posted By: dsmith41
I have been running a 0w30 (group IV, if it matters) oil for a while but I want to switch to a 5W-40 (group III, if it matters) oil soon just because it is much cheaper and still a great oil. But I am wondering if there will be much difference between these two oils in the dead of winter. Where I live, temps can drop to between -10 and 0 easily. It's not arctic by any means but still cold.

I know there is a difference between the two oils in the lab but I don't drive my pickup in a lab. Will it make a difference in my driveway?
You should look at the MRV cP pumpings specs. The 0w does not mean much at all. Just noted that GC has surprisingly high low temp pumping viscosity. So its not really a 0W at all more like a 10w! ( GC's ASTM-D 4684 listed as 60,000cSt at -40) Castrol Edge 5w30 is 11,5K at -35degC,

 

[ekpolk]

Where I live -- virtually none. I actually look at the vis in centistokes at 40C as, in my case, being more important than the "w" rating. I do this as my chances of challenging an oil's pumpability when cold is virtually nil. If we get to that point in Florida, I'll be selling campsites to expat Canadians at a high premium. Patman, you'll always be welcome to pitch a tent in my backyard, at the family discount rate!

 

[BuickGN]

Originally Posted By: ekpolk
Where I live -- virtually none. I actually look at the vis in centistokes at 40C as, in my case, being more important than the "w" rating. I do this as my chances of challenging an oil's pumpability when cold is virtually nil. If we get to that point in Florida, I'll be selling campsites to expat Canadians at a high premium. Patman, you'll always be welcome to pitch a tent in my backyard, at the family discount rate!

I agree. For our type of climates, the 40C number is much more valuable. We have some days where the first "cold" start is at the 40C number.

 

[ekpolk]

Originally Posted By: BuickGN
Originally Posted By: ekpolk
Where I live -- virtually none. I actually look at the vis in centistokes at 40C as, in my case, being more important than the "w" rating. I do this as my chances of challenging an oil's pumpability when cold is virtually nil. If we get to that point in Florida, I'll be selling campsites to expat Canadians at a high premium. Patman, you'll always be welcome to pitch a tent in my backyard, at the family discount rate!

I agree. For our type of climates, the 40C number is much more valuable. We have some days where the first "cold" start is at the 40C number.


I should also add that my cars are garaged (except for the poor Prius, now in my 20 year-old son's hands, and living "on the street"). Even on our worst day, which here would be ~+20F, my first start of the day will be at maybe 40-50F inside the garage just from the residual left from the previous days engine heat. Pumpability? Not a problem here.

Patman, I've been having a fit of conscience since that last post -- you can pitch for free here if it ever comes to that (as I envision glacier grinding into the side of your house. . .).

 

[Colt45ws]

I wish they would publish visc at some in between number like 0C. I could use that around here.

 

[dsmith41]

The vehicle is a Ford Ranger 4.0 and is my daily driver. The manual calls for a 5w30 oil so I figured a 5W-40 oil would be fine. Rotella is what I am wanting to run.

 

[CATERHAM]

Originally Posted By: Onmo'Eegusee
I wish they would publish visc at some in between number like 0C. I could use that around here.



I agree.

It's been discussed before, but if the first number of an SAE multi-vis grade (0, 5, 10 or 20) was the actual kinematic vis in cSt's it would be much more informative.
As it stands, the oil with the lowest vis at 40C will have the lowest vis at 0C assuming the VI is reasonable high and that is the number I look at in my climate when comparing different oils. If you want to know more precisely use the Widman Vis graph to calculate the 0C viscosity.

 

[CATERHAM]

DSmith, Rotella 5W-40 is a very robust oil and with a 40C vis (I'm guessing) of around 90 cSt vs 50 to 65 cSt of a typical 5w30 it will be very much heavier at sub freezing temps.
This would not be a good winter oil choice.

 

[BuickGN]

Originally Posted By: CATERHAM
DSmith, Rotella 5W-40 is a very robust oil and with a 40C vis (I'm guessing) of around 90 cSt vs 50 to 65 cSt of a typical 5w30 it will be very much heavier at sub freezing temps.
This would not be a good winter oil choice.


Depends on the winter. I would run it during a winter here no problem.

 

[mechtech2]

dsmith41 - Even at temps not as cold as -10F, you engine will like the flow of the 0-30 compared to the 5-40.
If you are looking for a cheaper alternative to expensive 0-30, use a synthetic 5-30 instead. Why jump to a 5-40?

 

[dsmith41]

Originally Posted By: mechtech2
dsmith41 - Even at temps not as cold as -10F, you engine will like the flow of the 0-30 compared to the 5-40.
If you are looking for a cheaper alternative to expensive 0-30, use a synthetic 5-30 instead. Why jump to a 5-40?


Because I have seen a lot of great used oil analysis from HDEOs and I want to give them a try. They seem big on additive package, small on price. It will also be an effort to simplify things as I use Rotella in my motorcycle.

My owner's manual recommends a 5w30 so I don't think the 5w oil should be a problem even though morning temps can get to -10 with the wind chill in my area of Nebraska. At operating temp, the 5w40 would be more viscous but would it cause a problem?

I looked at tech specs for the two oils:

Mobil 1 0w30: cSt@ 100* C is 11.0

Rotella 5w40: cSt@ 100* C is 15.5

 

[21Rouge]

Originally Posted By: dsmith41
My owner's manual recommends a 5w30 so I don't think the 5w oil should be a problem even though morning temps can get to -10 with the wind chill in my area of Nebraska.


Remember wind chill is not a concern to machines, only to warm blooded creatures such as you and me....or is that you and I?

 

[daman]

I would say there's going to be a slight advantage to using the 0w30 in the winter,i would use it over the 5w40 for sure.

 

[Gary Allan]

Mobil 1 0w30
SAE Grade 0W-30
Viscosity, ASTM D 445
cSt @ 40ºC 63.1
cSt @ 100ºC 11.0

Shell Rotella® T Synthetic
SAE Viscosity Grade
5W-40
Viscosity
@ 40°C cSt 95
100°C cSt 15.5

You've got roughly 3X the operating visc in difference @ 40C. That is, @ 40C you're using 3x energy it takes to pump Mobil 1 0w30 @ 100C in added load. The spread keeps on going.

The effect on fuel economy will depend on your trip length.

 

[ionbeam22]

For winter service I would want to be using the 0W oil, and would probably add some MMO to enhance cold cranking.

 

[oilyriser]

Was the motor in question back spec'd for 5w-20, by any chance?

 

[river_rat]

I used to run 10W all year before 5W got popular. I would just use whatever brand you like.
Originally Posted By: ekpolk
I'll be selling campsites to expat Canadians at a high premium.

How about us midwesterners? If this global cooling keeps up, Florida is going to get crowded in 5-10 years.