My 2010 did not have it. I thought they started on the 4th generation?
Are Hybrids really hard on oil?
- Thread starter Ed_Flecko
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All of the 3rd gen Prius have it.
Hmm, looking at ToyoDIY you appear to be correct. I didn't remember seeing it when I did the head gasket a couple years ago.
True and let’s not forget that crankcase speeds time in vacuum
My experience with my 23. Corolla cross is that ic will start up as I a, rolling out of the driveway or soon after I start down the street, it is about half a mile to my turn out the neighnorhood and it usually shuts down there for a moment and starts running when demanded. The coolant gets up to temp that fast in the engine circuit. I drive another 5 miles to the interstate at about 55. The engine will run and cycle on demand for the first 3 miles more if I want heat. The last two miles is a downhill run to the interstate where the hybrid battery enjoys a good charge and the ic shuts down. I then drive about 45 miles of interstate 65-70 exit and drive 5 miles to a worksite. I average 47 mpg ajd run 10 k mile intervals I do this round trip 5-6 days a week. The ev mode is only 25-30% most days heavy traffic makes it 50%. I can’t think of a better driveline for me right now.
Moisture in the oil is definitely happening in my 2024 Prius plug in hybrid. I can see mayo emulsion under the oil fill cap in winter months. I try to ensure that the engine runs long enough to heat up when it starts and longer trips also help to reduce the emulsion.
I don’t know if the moisture will result in any significant wear issues. I’m currently using 0W16. The engine doesn’t run much - a tank of gas typically lasts me 2 to 3 months (2000 to 3000 miles).
I don’t know if the moisture will result in any significant wear issues. I’m currently using 0W16. The engine doesn’t run much - a tank of gas typically lasts me 2 to 3 months (2000 to 3000 miles).
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Perhaps on purpose don't plug in your phev once in a while and drive it around until all bothering issues are negligible?
JHZR2
Staff member
Not wrong in cool conditions. But I’ve seen water temperatures over 200. I used to have the gauge up all the time but became kind of boring. Easy cruising doesn’t use much power or make much heat.
If some hybrids are moving continuously at speeds above about 40 mph on level terrain, the engine runs continuously. In that case, why shouldn't the oil temperature be nearly the same as in a nonhybrid under the same conditions?
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0w8 n 0w16 basically were formulated to be used in hybrids also from the get go imo. old prius last forever.
i think we are safe running whatever has worked so far.
i think we are safe running whatever has worked so far.
Just because the engine isn't burning as much gas, generally. Most hybrids (not all but most) have a more efficient atkinson-cycle engine that's engineered for peak MPG rather than performance. Some non-hybrids have atkinson or part-time atkinson engines though and they just get a bit better MPG. (And if you burn less gas to travel at the same speed, you will reduce the size of the heat load for the radiator to shed.)
Still I think people in this thread are forgetting about the thermostat. Engines can and do run with the thermostat fully closed in certain conditions. (All kinds of engines, not just hybrids.) The thermostat is designed to keep heat in the engine itself and its oil when it needs to keep heat inside, while being able to shed heat when it needs to shed heat. In extremely cold conditions it's actually not uncommon to feel a cold radiator after a long drive, because the engine is warmed up but sheds enough heat through the block itself and through the heater (because the heater is usually blasting inside the car during these kinds of drives). I would even find this to be true after a very cold drive in my old BMW X5 which would struggle to get over 20mpg on the highway (i.e. a very inefficient car).
That is the same situation as what has been described earlier in this thread, when a very efficient hybrid vehicle today has a cool or cold radiator after a highway drive with the engine running. The only difference is what outside temperature allows the vehicle's engine to cool itself without using the radiator. For a very efficient car, it could be 70 degrees, but for a very inefficient car like a BMW X5, it could be 5 degrees or minus-5 or something like that.