Exactly!
If the HVAC is calling for heat that will force ICE start.
If you want to take advantage of EV operation on start up just turn the HVAC off before you shut the car down.
Are Hybrids really hard on oil?
- Thread starter Ed_Flecko
- Start date
If the HVAC is calling for heat that will force ICE start.
If you want to take advantage of EV operation on start up just turn the HVAC off before you shut the car down.
Not correct. It will not turn off the engine until the catalysts are warmed up, but the engine absolutely cycles while it is still cold on all of my new Toyota hybrids.
Here's a data point: I own a 2015 Chevrolet Volt. Some would say that it's a hybrid. It is, kind of.
Almost all of the time, it runs entirely on electricity and the engine never spins. Only when the battery goes flat does the engine turn on. And, the only times we go far enough to discharge the battery, we go far enough to fully heat up the engine. Additionally, the engine control computer gently wakes the engine up, and runs it slowly for several minutes to give the engine time to warm up.
As a result, this car is about as easy on a motor oil as a car can be. Living in Southern California helps - moderate temperatures that are never too hot or too cold.
Almost all of the time, it runs entirely on electricity and the engine never spins. Only when the battery goes flat does the engine turn on. And, the only times we go far enough to discharge the battery, we go far enough to fully heat up the engine. Additionally, the engine control computer gently wakes the engine up, and runs it slowly for several minutes to give the engine time to warm up.
As a result, this car is about as easy on a motor oil as a car can be. Living in Southern California helps - moderate temperatures that are never too hot or too cold.
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I have not observed this in my Toyota hybrid. What is the "warm up" temp for the catalysts? Mine turns off regardless of catalysts temp imo.
Yes, I never kept my Prius in the garage and live in an area where it gets pretty cold. So I would always have the heat on.
Now I wish I still had it so that I could datalog the catalyst and the coolant temp and see when it allows the engine to turn off.
That car had a relatively small battery, and couldn't really accelerate that fast with just the battery.
However, it would keep the engine at a constant load and RPM until it was warmed up. It would actually move the car only with the battery for a couple of minutes, until the battery was low or if you had to get on the highway right after starting the car. I always interpreted that as getting the engine up to temperature before allowing the start/stop function to be used.
I wonder what the EPA requires to get a new engine certified, as far as catalyst temperatures go, before the start/stop function is allowed to be used. Or if they regulate it at all. As you all can see, I'm not an expert but I am very curious and would be happy to be educated on this.
Carlostrece
$100 Site Donor 2025
After driving it for 15+ min....
Look at the dipstick and underside of oil filler cap. If there's too much water in the oil you'll see creamy, frothy, chocholate milkshake looking oil on the dipstick and underside of oil filler cap. Then you'll be able to see if there's water in the oil.
If the oil looks thinner than normal for the viscosity grade and/or smells like gasoline, you then know it has fuel contamination.
Visual appearance and smell provide clues if you know how to interpret them.
Look at the dipstick and underside of oil filler cap. If there's too much water in the oil you'll see creamy, frothy, chocholate milkshake looking oil on the dipstick and underside of oil filler cap. Then you'll be able to see if there's water in the oil.
If the oil looks thinner than normal for the viscosity grade and/or smells like gasoline, you then know it has fuel contamination.
Visual appearance and smell provide clues if you know how to interpret them.
Carlostrece
$100 Site Donor 2025
I just use regular 5w30 full synthetic in my mom's Prius. Any good brand will do fine.
I have a roster of favorites (any of which will do):
Havoline ProDS Lifelong (High Mileage)
Maxlife Extended Protection High Mileage Full Synthetic
Quaker State High Mileage Full Synthetic
Maxlife High Mileage Full Synthetic
NAPA Full Synthetic
I'm sure Pennzoil or Mobil 1 high mileage oils would also be fine, but I don't buy those. Probably any good oil full synthetic is fine, especially any good High Mileage Full Synthetic oil is fine. I would also consider High Mileage Full Synthetic oil by Warren (Supertech, Kirkland, Amazon Basics).
When my cousin checks the dipstick and changes oil, we've never seen signs of water or fuel contamination. So regular FS oil has been working fine.
Her Prius currently has NAPA Full Synthetic in it. My Buick currently has a mix of 3 quarts Maxlife Blend, 1 quart NAPA Full Synthetic. My neighbors Honda CRV has Maxlife Blend in it. My other neighbor's car has Quaker State High Mileage Full Synthetic in it. All of them 5w30.
In future, they will all be switched to Havoline Lifelong 5w30. If Lifelong is unavailable, my next choice would be Maxlife Extended Protection High Mileage Full Synthetic.
Oil made speficically for Hybrid is unnecessary, IMO.
I have a roster of favorites (any of which will do):
Havoline ProDS Lifelong (High Mileage)
Maxlife Extended Protection High Mileage Full Synthetic
Quaker State High Mileage Full Synthetic
Maxlife High Mileage Full Synthetic
NAPA Full Synthetic
I'm sure Pennzoil or Mobil 1 high mileage oils would also be fine, but I don't buy those. Probably any good oil full synthetic is fine, especially any good High Mileage Full Synthetic oil is fine. I would also consider High Mileage Full Synthetic oil by Warren (Supertech, Kirkland, Amazon Basics).
When my cousin checks the dipstick and changes oil, we've never seen signs of water or fuel contamination. So regular FS oil has been working fine.
Her Prius currently has NAPA Full Synthetic in it. My Buick currently has a mix of 3 quarts Maxlife Blend, 1 quart NAPA Full Synthetic. My neighbors Honda CRV has Maxlife Blend in it. My other neighbor's car has Quaker State High Mileage Full Synthetic in it. All of them 5w30.
In future, they will all be switched to Havoline Lifelong 5w30. If Lifelong is unavailable, my next choice would be Maxlife Extended Protection High Mileage Full Synthetic.
Oil made speficically for Hybrid is unnecessary, IMO.
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I'll have to check when I get my hands on my MIL's RX350h again. Modern catalytic converters warm up pretty quickly.
On a cold start, the RX350h will shut off the gas engine before it reaches the end of my street.
Encourage you to take a look at some of the info I posted in this thread. Afton is a major additive supplier who is the brains behind many of the oils you see on the shelf today:
Interesting read.Encourage you to take a look at some of the info I posted in this thread. Afton is a major additive supplier who is the brains behind many of the oils you see on the shelf today:
Maybe my hybrid has benefited from being used regularly for highway drives of various lengths which allow the ICE to reach and maintain a normal operating temperature for considerable time?
It would seem that there could be problems with hybrids operated only in local conditions, especially with PHEVs.
Hard on coolant, I believe
Correct. The short trip driven hybrids, especially the plug-in models, are the main issue.
"Hard on" and "dependent on for longevity" are two different things.
JHZR2
Staff member
Such a claim is silly because it doesn’t indicate a timeframe. I’m quite sure that when I drive my longer trips that it hits temperature. Sure it could fluctuate more I suppose. But time at temperature is key.
I could claim the same thing for a short tripped ICE. Which would also need precautions.
That said, I’ve kind stated that I think my hybrid is harder on the oil. The fact that I could be driving hard, accelerating or climbing a hill, and then with a change in load the engine just shuts off, would indicate to me that hot spots and other anomalous things could happen.
I’d like to see a compare of the Mobil 1 hybrid vs Mobil 1 ESP.
My new TX500h hovers around 190f under most conditions, even on long highway drives. I think I have seen it hit 200F once.
I haven't monitored our RX350h very closely but judging by how cool the oil is after a long drive, I doubt it's much different.
JHZR2
Staff member
I’m not a believer that oil must spend massive amounts of time over 212 to drive off moisture.
The difference in 190 vs 200 (assuming oil temperature, though in many vehicles we could be talking the same about water) may mean a bit more effective management, or not. Too many factors to consider.
It’s a reason why UOA bring value even if not doing trends. If you assume that the values for fuel and water are reasonably accurate, and don’t sweat them being perfectly exact but more of a yes/no or a how bad is it indication, you can glean some insights into if it even matters.
As I’ve mentioned, I’d be more concerned about hotspots due to rapid shutdown after sustained load, then water or fuel in oil in most climates.
Visible-sized water droplets in oil are very resistant to evaporation and forming emulsions in stationary hot oil that is < 100 C. If the oil and water droplets undergo shear, it increases the emulsion tendency, which allows for increased water evaporation rate. If a water droplet gets hot enough, it suddenly turns to vapor and the vapor portion is ejected from the oil. I’ve observed all of this many times in bench tests that started with a water droplet in oil, not an emulsion. What I don’t know is under what conditions, if possible, visible-sized water droplets sink to the bottom of an oil pan. Most of us have seen pictures of milkshake emulsions on the underside of oil fill caps, which forms from extremely humid air in contact with oil, rather than from an intrusion of visible-sized water droplets.
Significant concentrations of water in hot motor oil results in chemical reactions with some metallic additives, causing visible white solid precipitate to form. I don’t know if it’s from ZDDP and/or detergents and/or MoDTC.
As the lady who designed GM’s oil life monitor said, if you want to ruin an oil quickly on a mileage basis, give it the old grandma duty cycle. Every week, only take short trips to/from church and grocery store.
Significant concentrations of water in hot motor oil results in chemical reactions with some metallic additives, causing visible white solid precipitate to form. I don’t know if it’s from ZDDP and/or detergents and/or MoDTC.
As the lady who designed GM’s oil life monitor said, if you want to ruin an oil quickly on a mileage basis, give it the old grandma duty cycle. Every week, only take short trips to/from church and grocery store.
Starting with 2010 model year.
Otherwise, good post!
When it allows the engine to turn off is complicated. Following a cold start, the programming won't allow the engine to turn off during the first one minute. In fact, during that minute, it tries to avoid using the engine to drive the wheels, unless you insist by pressing the accelerator harder. Then there's a phase in which the engine stops only when the wheels are stopped (or nearly stopped) and no cabin heat is requested. Next comes a period in which it seems unpredictable whether the engine will stop when the car is coasting with no demand for power to the wheels. Finally, after coolant temperature reaches about 152°F, the engine will usually stop when it isn't needed.
You're certainly correct that acceleration on only the battery is extremely modest in a "regular" Prius.