Yep. The difference will never be outside of the measurement error in the first place.
Shell Rotella 5w-40 for 2007 Prius?
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Yep, physics say the thicker Rotella will cause about a 1.5% loss in MPG. https://bobistheoilguy.com/forums/ubbthreads.php/topics/3912866/What_sort_of_fuel_economy_will
Originally Posted By: Sam_Julier
The Prius is spec'd with an high VI 0W20 for lots of reasons. If 5W40 was the perfect oil for this engine the Toyota engineers would have spec'd it. Use the oil Toyota specified. For background read CATERHAM's posts on high VI oils.
Can you expound, please, on what these reasons might be?
Thanks, everyone.
The Prius is spec'd with an high VI 0W20 for lots of reasons. If 5W40 was the perfect oil for this engine the Toyota engineers would have spec'd it. Use the oil Toyota specified. For background read CATERHAM's posts on high VI oils.
Can you expound, please, on what these reasons might be?
Thanks, everyone.
Originally Posted By: Eddie
5w40 will work but, certainly not the best for the engine when it is spec'd for 0w20. Ed
According to the manual, the engine is spec'd for 5w-30 mineral oil.
Can a 5w-40 sun really be inadequate, given the original spec?
5w40 will work but, certainly not the best for the engine when it is spec'd for 0w20. Ed
According to the manual, the engine is spec'd for 5w-30 mineral oil.
Can a 5w-40 sun really be inadequate, given the original spec?
Originally Posted By: alarmguy
I doubt it will do any harm, might even be just fine to very good for your engine but your engine is spec'd for a 5/30 oil so Im not sure why you would go up to a 5/40, even more so in a cool climate of Seattle.
Personally I would follow the manual and use the 5/30.
Here is the Toyota PDF on oil weight for the 2007 Prius, Click Here, Page 432
This car is entirely used as an Uber/Lyft vehicle and is run hard for 4-8 hours at a time. I change the oil every 3,000 miles with the 5w-30 but thought that the Rotella that I use in my other vehicles might be a better choice and might allow longer change intervals. Can a 5w-30 mineral oil really be better in this use than a 5w-40 synth?
I doubt it will do any harm, might even be just fine to very good for your engine but your engine is spec'd for a 5/30 oil so Im not sure why you would go up to a 5/40, even more so in a cool climate of Seattle.
Personally I would follow the manual and use the 5/30.
Here is the Toyota PDF on oil weight for the 2007 Prius, Click Here, Page 432
This car is entirely used as an Uber/Lyft vehicle and is run hard for 4-8 hours at a time. I change the oil every 3,000 miles with the 5w-30 but thought that the Rotella that I use in my other vehicles might be a better choice and might allow longer change intervals. Can a 5w-30 mineral oil really be better in this use than a 5w-40 synth?
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Originally Posted By: Bandito440
It'll be just fine. You might lose 2% fuel economy. Too much panic here.
I like the idea of using one oil for all vehicles. Your Prius is out of warranty. If you've got a diesel truck or something turbocharged that does well with 5w-40, go for it.
1994 Jeep Cherokee, plus a small fleet of Moto Guzzi motorcycles. No diesel trucks.
It'll be just fine. You might lose 2% fuel economy. Too much panic here.
I like the idea of using one oil for all vehicles. Your Prius is out of warranty. If you've got a diesel truck or something turbocharged that does well with 5w-40, go for it.
1994 Jeep Cherokee, plus a small fleet of Moto Guzzi motorcycles. No diesel trucks.
I wouldn't use it on my Prius, that's for sure
If you are changing every 3K, you can use a good dino oil and it will serve just fine. Even if you extend to 5K you could still use a good dino oil. If you are stretching to once a year changes, I'd be looking at M-1 EP or something similar.
You are not likely to save money, but you might save time under the car
You are not likely to save money, but you might save time under the car
The Toyota schedule does not increase oil and filter change frequency with severity for the 2007 Prius. Some other items increase frequency (EG Air filter, check ball joints and so forth)
It specifies 5000 miles with conventional 5/30. Absolutely no point in doing it every 3000.
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
It specifies 5000 miles with conventional 5/30. Absolutely no point in doing it every 3000.
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
Originally Posted By: DuckRyder
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
this is very true. when i got new tires (obviously less LLR than used OEM) for my prius, it initially messed up my city MPG by whooping 15% (65mpg->55mpg). there is no way you would see that in a regular car. now after 30,000 miles on the tires, the hit is more reasonable 5%.
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
this is very true. when i got new tires (obviously less LLR than used OEM) for my prius, it initially messed up my city MPG by whooping 15% (65mpg->55mpg). there is no way you would see that in a regular car. now after 30,000 miles on the tires, the hit is more reasonable 5%.
Originally Posted By: DuckRyder
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
There still won't be a "huge" difference. Viscosity affects fuel economy. That's well established. What's also well established is that when it comes to calculating fuel economy in the real world, the error bars are what are "huge."
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
There still won't be a "huge" difference. Viscosity affects fuel economy. That's well established. What's also well established is that when it comes to calculating fuel economy in the real world, the error bars are what are "huge."
Originally Posted By: lubricatosaurus
Rotella T6 will work very well. Not that much difference hot. Thicker oil films are not a problem.
There is a large difference in hot viscosity between a HTHSV 2.6cP oil 0W/5W-20 and the 4.0cP HTHSV of Rotella, the problem being reduced oil flow.
But the biggest viscosity difference will be on start-up where the Rotella 5W-40 will be particularly unsuitable for a hybrid application.
The best oil for the Prius is TGMO 0W-20 for which it was specifically developed.
A secondary choice any other OTC 0W-20.
Rotella T6 will work very well. Not that much difference hot. Thicker oil films are not a problem.
There is a large difference in hot viscosity between a HTHSV 2.6cP oil 0W/5W-20 and the 4.0cP HTHSV of Rotella, the problem being reduced oil flow.
But the biggest viscosity difference will be on start-up where the Rotella 5W-40 will be particularly unsuitable for a hybrid application.
The best oil for the Prius is TGMO 0W-20 for which it was specifically developed.
A secondary choice any other OTC 0W-20.
Originally Posted By: CATERHAM
There is a large difference in hot viscosity between a HTHSV 2.6cP oil 0W/5W-20 and the 4.0cP HTHSV of Rotella, the problem being reduced oil flow.
Rubbish, how is this a problem ?
Bearings will take what they need, nothing is ever gained by ensuring the full volume of the oil pump is jemmed through them.
Originally Posted By: CATERHAM
But the biggest viscosity difference will be on start-up where the Rotella 5W-40 will be particularly unsuitable for a hybrid application.
The best oil for the Prius is TGMO 0W-20 for which it was specifically developed.
A secondary choice any other OTC 0W-20.
Specifically, which of the various multitude of TGMOs was specifically designed for this Prius (which ACTUALLY specifies 5W30) ???
I'm not saying that Rotella is the ideal oil for the application, it WILL cost a little fuel, for sure, but scaremongering it as "particularly unsuitable" is plain wrong.
There is a large difference in hot viscosity between a HTHSV 2.6cP oil 0W/5W-20 and the 4.0cP HTHSV of Rotella, the problem being reduced oil flow.
Rubbish, how is this a problem ?
Bearings will take what they need, nothing is ever gained by ensuring the full volume of the oil pump is jemmed through them.
Originally Posted By: CATERHAM
But the biggest viscosity difference will be on start-up where the Rotella 5W-40 will be particularly unsuitable for a hybrid application.
The best oil for the Prius is TGMO 0W-20 for which it was specifically developed.
A secondary choice any other OTC 0W-20.
Specifically, which of the various multitude of TGMOs was specifically designed for this Prius (which ACTUALLY specifies 5W30) ???
I'm not saying that Rotella is the ideal oil for the application, it WILL cost a little fuel, for sure, but scaremongering it as "particularly unsuitable" is plain wrong.
Originally Posted By: Gokhan
Again, go with a more premium oil like M1 0W-40 SN. Rotella is cheap Group III intended for 18-wheelers. M1 0W-40 SN has Group IV and V in addition to III+ and is intended for most demanding engines.
The ENGINE in a tractor costs more than the average car but you claim "cheap oil" should be used in them? HUH?
Again, go with a more premium oil like M1 0W-40 SN. Rotella is cheap Group III intended for 18-wheelers. M1 0W-40 SN has Group IV and V in addition to III+ and is intended for most demanding engines.
The ENGINE in a tractor costs more than the average car but you claim "cheap oil" should be used in them? HUH?
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Originally Posted By: friendly_jacek
Originally Posted By: DuckRyder
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
this is very true. when i got new tires (obviously less LLR than used OEM) for my prius, it initially messed up my city MPG by whooping 15% (65mpg->55mpg). there is no way you would see that in a regular car. now after 30,000 miles on the tires, the hit is more reasonable 5%.
That's one of the things that puzzled me. Given that the Prii are powered by a faux Atkinson-cycle engine with low compression, how does that affect all this?
Originally Posted By: DuckRyder
I think that you guys quoting Shannow's post may not be considering that Prius don't necessarily react like "normal" cars where fuel economy is concerned.
this is very true. when i got new tires (obviously less LLR than used OEM) for my prius, it initially messed up my city MPG by whooping 15% (65mpg->55mpg). there is no way you would see that in a regular car. now after 30,000 miles on the tires, the hit is more reasonable 5%.
That's one of the things that puzzled me. Given that the Prii are powered by a faux Atkinson-cycle engine with low compression, how does that affect all this?
Originally Posted By: Gokhan
... Rotella is cheap Group III intended for 18-wheelers.
Credibility gone ...
... Rotella is cheap Group III intended for 18-wheelers.
Credibility gone ...
Originally Posted By: greguzzi
plus a small fleet of Moto Guzzi motorcycles.
Pictures Please !!
I do love a nice Moto Guzzi……...
plus a small fleet of Moto Guzzi motorcycles.
Pictures Please !!
I do love a nice Moto Guzzi……...
Originally Posted By: Shannow
Originally Posted By: CATERHAM
There is a large difference in hot viscosity between a HTHSV 2.6cP oil 0W/5W-20 and the 4.0cP HTHSV of Rotella, the problem being reduced oil flow.
Rubbish, how is this a problem ?
Bearings will take what they need, nothing is ever gained by ensuring the full volume of the oil pump is jemmed through them.
Originally Posted By: CATERHAM
But the biggest viscosity difference will be on start-up where the Rotella 5W-40 will be particularly unsuitable for a hybrid application.
The best oil for the Prius is TGMO 0W-20 for which it was specifically developed.
A secondary choice any other OTC 0W-20.
Specifically, which of the various multitude of TGMOs was specifically designed for this Prius (which ACTUALLY specifies 5W30) ???
I'm not saying that Rotella is the ideal oil for the application, it WILL cost a little fuel, for sure, but scaremongering it as "particularly unsuitable" is plain wrong.
And who are you?
Oh right, you're that guy who actually believes oil flow doesn't matter! But that shouldn't come as a total surprise from someone who used to run a 15W-50 in a late model GM V6, who thinks a mono grade (99 VI) dino oil is best for track use and running a 20 grade oil even when specified will shorten engine life, just to mention few of your motor oil beliefs.
So yes you are indeed one of the BITOG go to guys if you want a totally antedeluvian viewpoint on motor oil.
And for the few that don't know, the 20 grade has been back spec'd to the first gen' Prius.
Originally Posted By: CATERHAM
There is a large difference in hot viscosity between a HTHSV 2.6cP oil 0W/5W-20 and the 4.0cP HTHSV of Rotella, the problem being reduced oil flow.
Rubbish, how is this a problem ?
Bearings will take what they need, nothing is ever gained by ensuring the full volume of the oil pump is jemmed through them.
Originally Posted By: CATERHAM
But the biggest viscosity difference will be on start-up where the Rotella 5W-40 will be particularly unsuitable for a hybrid application.
The best oil for the Prius is TGMO 0W-20 for which it was specifically developed.
A secondary choice any other OTC 0W-20.
Specifically, which of the various multitude of TGMOs was specifically designed for this Prius (which ACTUALLY specifies 5W30) ???
I'm not saying that Rotella is the ideal oil for the application, it WILL cost a little fuel, for sure, but scaremongering it as "particularly unsuitable" is plain wrong.
And who are you?
Oh right, you're that guy who actually believes oil flow doesn't matter! But that shouldn't come as a total surprise from someone who used to run a 15W-50 in a late model GM V6, who thinks a mono grade (99 VI) dino oil is best for track use and running a 20 grade oil even when specified will shorten engine life, just to mention few of your motor oil beliefs.
So yes you are indeed one of the BITOG go to guys if you want a totally antedeluvian viewpoint on motor oil.
And for the few that don't know, the 20 grade has been back spec'd to the first gen' Prius.
Seems it's all a fight between memory & past practices, and newer oil chemistry. Us old guys know what HAS worked for us for decades w/o problem. We are loath to give up strongly held beliefs (not necessarily facts) that fly in the face of the "new stuff".
But, among some of those old beliefs that work is that single weights do work in race motors. No viscosity improvers to shear down, etc. In the case of fuel drag cars, the oil is pre-heated to op temp before it is poured in the tank between rounds, so it's at op temp when the engine fires...
Roundy-round cars do have cold starts, but only once a night. Some come with priming pumps that have full pressure when the starter is engaged.
As far as flow being critical to lubrication, it's not that simple. You can have lubrication w/o flow just like using an oil can on a bolt, or gravity cups on rods and mains in stationary engines, or accumulated mist in 2-strokes...
But in general, in modern high speed engine designs, you need flow to replenish the oil slung away, and to help with the oils cooling effect by supplying cooler fresher oil. Flow itself does not lubricate ...
But, among some of those old beliefs that work is that single weights do work in race motors. No viscosity improvers to shear down, etc. In the case of fuel drag cars, the oil is pre-heated to op temp before it is poured in the tank between rounds, so it's at op temp when the engine fires...
Roundy-round cars do have cold starts, but only once a night. Some come with priming pumps that have full pressure when the starter is engaged.
As far as flow being critical to lubrication, it's not that simple. You can have lubrication w/o flow just like using an oil can on a bolt, or gravity cups on rods and mains in stationary engines, or accumulated mist in 2-strokes...
But in general, in modern high speed engine designs, you need flow to replenish the oil slung away, and to help with the oils cooling effect by supplying cooler fresher oil. Flow itself does not lubricate ...
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