Prius Prime engine oil change intervals

Don't know about Rav4 Prime, but PP shows EV driving ratio on the Drive Monitor. If you never reset it, then the number corresponding to ODO is for the lifetime. The EV ratio includes the EV portion of the HV mode drive

The photo below is from my 2017 PP. 60% EV ratio means 40% Engine on. So, for 36Kmiles ODO, 40% or 14.4Kmiles was on the engine. But, if I keep my Prime longer than 3 years, I will just follow the manual which says oil change 10K miles or 1 year whichever comes first.


I commented on the Gen4 thread, but Prius (PP or any other Prius family cars) has no transmission (or transaxle) fluid change recommendation interval. I changed my Gen3 at 30K, but for PP which I will not likely to keep longer than 3 years, I won't bother with it, unless I change my mind and decide to keep it for a long haul.

 

I'm just doing it the lazy way and going by the odometer. But since I only drive ~5,000 a year, it works out to the once a year I would have to anyway. I dont think it NEEDS to be changed yearly especially with EV driving and using the new synthetic oils, but $25 of oil is cheep insurance to cover more than $2500 engine / generator / traction battery / labor replacement costs.

 

I'd stick with the Toyota USA recommendation, at least for the duration of the power train warranty. I believe that's yearly or 10K miles, whichever comes first. Keep a lthorough log, and all supply receipts.

One thing I do which maybe covers my butt better: purchase oil and filter through dealership parts department, where my car is registered. That way dealership has same receipts as me.

FWIW, with Honda vehicles, which have a Maintenance Minder system, they recommend to at least change the oil yearly, regardless of what Maintenance Minder says, unless the vehicle's completely mothballed, I suppose.

Maintenance Minder info

 

you could get an oil analysis done

 

I agree with you completely, especially if you plan to keep your car for a long time. From what I have read, the fluid is dark even at very early transmission fluid change, but that does not mean it will not last for 100Kmiles or longer without changing. I for one had the WS ATF changed on my Gen3 at 30K miles and asked for the fluid sample. It was dark brown to black not transparent pink color. But Toyota's official recommendation has nothing on transmission fluid change. I have never had any car Toyota or otherwise that I had to have transmission work done. I have not yet read here any older Prius needing transmission repair. For my PP, knowing I will not keep the car longer than 3 years/3600 miles top, I am not going to worry about what is not required maintenance item. All I am going to do on my PP is routine maintenance recommended in the manual which is annual (or 10Kmiles) oil/filter changes. that will be it.

 

I did a transaxle fluid change at one year mark (around 16K kms), and it was noticeable darker than new fluid. Then, a second, and a third, each time at longer interval, and with each time there was less darkening of the fluid, to the point I think I'm done.

Bottom line from my perspective: the first change can't happen too soon. but from there on the fluid is much more durable, might be more durable, purely judging from appearance.

 

tranny is the most reliable prius part, but prime has a clutch. idk if that matters

 

I experienced the same, on my 2012 Prius C. First ATF change was at 20K, it came out black cherry red - almost brown. The second change was at 75k, ATF was darker than new, but cleaner than the 20K mile change. The car was totaled at 92k.

I plan on following the same procedure on this 2021 Prime; it's cheap insurance.

BTW; lots of driving through the Sierra mountains in that Prius C; 8 years in the hot Sacramento summers.

 

It makes me crazy that the engine maintenance interval is the same for a Prime as for a straight hybrid. When the engine isn’t running the oil and other fluids and their associated filters aren’t exposed to extraordinary heat. There is no sell by date on these items. It is relatively easy math to calculate the miles on the engine if you know the MPG, miles driven to achieve that MPG, mpge, and Hybrid MPG. I wish Toyota would publish maintenance schedule for the ICE that is separate from the rest of the car. I had occasion to drive 1000 miles on hybrid only and found I got 59.6 mpg-h. We know the mpge is 199. That means at 40k miles my engine has seen 26k.

 

i just change mine once a year

 

I think for PHEVs toyota should display and build maintenance schedules based on ICE running hours and time like with farm equipment.

 

They could maybe try something sim to Hondas maintenance minder. It seems to monitor various parameters, including engine run Tim. FWIW Honda does say to change oil yearly, regardless.


Honda Maintenance Schedule Calculator | Honda Canada

 

I encourage all my friends and family to learn to do basic maintenance on their vehicles themselves. There's numerous reasons:

-Nobody cares for your vehicle like you do...it's usually the 2nd largest investment we have so, of course, we want to ensure we get a good return-on-investment (ROI).
-LOTS of issues with vehicles start small and, if not noticed, turn into big and expensive problems. (A valve cover develops a small leak because the gasket went bad...not a big deal, at first, but if left could lead to oil leakage which could lead to engine overheating which could lead to head gasket failure which could lead to thousands of dollars in repair costs which could've been avoided by replacing a $10 gasket.)
-An oil change can be expensive and time-consuming...making the appointment, having to either drop off your vehicle or waiting for it and let me tell a secret, even Toyota Dealerships have been known to buy the cheapest oil in bulk in order to raise profits. When you do the oil change yourself, you do it when YOU want to, using the oil YOU like, and you know it's done right. I've seen dealership, numerous times, mess up an oil change by overtightening drain plugs and filters/cartridges and even using the wrong oil. (They put 0W-20 in my new Prius that takes 0W-16 AND overfilled it by over half a quart. I only did it because it was free but I ended up re-doing the job as soon as I got home and I'm never letting those yahoos touch my car again.)

Every 6-months, or 5,000 miles, whichever comes first...then you won't worry about it. (Yes, even plug-in...STILL has the motor in there.)

 

Too with oil changes, the plastic underpanels with finicky fasteners take a beating from the "professionals". See "oil change info" link in my signature; it has some tips for taking care with the panels.

 

In every forum about PP and R4P the oil change interval question comes up. Easy to understand why. Simplest thing is to just follow the manual, especially while under warranty, and do it every 10K or 1 year. But we can't help but wonder if that's overkill. I did my first 'break in' oil change at just over 1K miles, refilling with Amsoil 0W-16. Then had the dealership do theirs at 10K. Before taking it to the dealership I drained some into a sample cup for Blackstone Labs. 8771 miles and 11 months on this oil. It was still translucent amber in color too.



I'll probably take another sample at the next 5K mile interval as a reference. I'm sure a person could stretch to 18mo if they really wanted to but it seems pointless. 1 year is an easier checkpoint to track.

 

I'm just going to do annual oil changes.
I only fill-up once a month; so assuming 500 miles/tank on ICE and 13 fill-ups per year. I'm only doing 6500 miles on the ICE. I purposefully rounded some numbers up and others down to add a margin of safety. I routinely get more than 1000 miles on one tank of gas, so I'll be below the OEM recommended 10K mile oil change interval but slightly above the 5k mile interval; the conservative people here use.

I'm comfortable with that.....