During the first few hundred miles, it's best practice for any engine to vary the rpm and load. This helps mate all the wear surfaces together properly: piston rings and cylinders, bearings and cam/crank journals, etc. This isn't just a Prius thing, it applies to any vehicle with an internal combustion engine. Running an engine constantly at the same rpm for many miles during the break in period is not fantastic for it. That being said, a modern Toyota engine is not the same as a domestic engine from 30 years ago when this break in procedure was critical. Back then, you could ruin an engine if you didn't break it in correctly. You're not going to be able to do that today. Even if you do everything wrong, the worst you're going to do is reduce the lifespan of the engine by a little bit. Instead of being able to go 400k miles before needing to be rebuilt, it might only go 350k. Changing your oil every 6m/5k is going to have a far greater effect on the lifespan of your engine than the break in period. That could be the difference between 350k and 125k. But if you want your new Prius to have the absolute best chance to get every mile possible, vary the speeds during your trip home. If you can, avoid interstate freeways for some/all of the route and use two-lane roads that force you to vary speeds. And feel free to accelerate to pass people; that's actually beneficial because it changes the load the engine is under. Don't be focused on getting max mpg on this first trip; that can come later. The other thing you can do if you want to maximize the life of the engine is do your first oil change after you get home. It won't dramatically change the lifespan of the engine, but it will help it just a little bit. In the end, it all depends on how long you plan to own the car and your personality type. If you only plan to own it 3-5 years, then none of this matters to you personally. Any negative effects will occur long after you've sold the car and moved on. In that case, the only reason to do this stuff is because you like to do things the best way they can be done. That's meaningless to some, hugely important to others, and everything in between to everybody else. You do you and don't let us tell you otherwise.
It says do not drive at the same speed for long periods in the owner’s manual: ■Breaking in your new Toyota To extend the life of the vehicle, observing the following precautions is recommended: ●For the first 200 miles (300 km): Avoid sudden stops. ●For the first 600 miles (1000 km): • Do not drive at extremely high speeds. • Avoid sudden acceleration. • Do not drive continuously in low gears. • Do not drive at a constant speed for extended periods.
It can be an indication for how much dirt is in the oil. For lubrication purposes, this isn't much of a 'thing' because as it turns out modern engines have oil filters to take out the big hunks. HOWEVER (comma!!!!!) Something is causing contamination in the EGR loops and in Variable valve timing, and other systems in a lot of not-very high mileage engines. This contamination occurs when dirt, debris, or sludge in the engine oil accumulates in an engines small oil passages and solenoids, which is why it can be beneficial to change the oil a little more often than the 7.5K to 10K oil change intervals that the OEMs are recommending. This isn't a "break-in oil" thing - which among car enthusiasts is the equivalent of "nursery water" for a first child. Most of the people who are worried about this probably trade out the car before it gets to 150,000 miles and even if you keep to the OEM maintenance practices and periodicities, and SKIP an oil change or two you're probably going to see 150,000 miles in a car without many problems. ^ That. If you're driving a NEW G5 instead of a NEW TO YOU G5 then odds are you're fairly young - since gas in your part of the country is relatively inexpensive and the G5 is not really built for 'old people joints.' I hope the 7-hour drive takes you out of the SE Toyota group of dealerships, and I would very strongly encourage you to FULLY READ read and FULLY UNDERSTAND the Warranty and Maintenance Guide and ask questions before EVER taking that car back to another Toyota dealership. Rant out. The trip back will not affect the longevity of your engine in the least no matter HOW you drive the car because home. The 'turd gen' (G3) engine problems and their premature failures resulted from a major design flaw which wrecks the ICE in the front nine, and even the G4 has issues which in some cases will cause an engine-out landing at a dealership from overheating. In both of these cases these conditions are aggravated by inattentive owners who operate with a 'closed hood' maintenance policy. Read the Guide and DO the things, and you have a quarter million mile car - EVEN WITH the design flaws that exist in ALL cars. Good Luck!
I did a super early oil change at 6 months because we have the PHEV, and I put maybe 2,000km on the engine in that time, intentionally running hybrid mode more often. But after that, we did the expected 12 month oil change. And now I only plan to change the oil once a year. The PHEV won't be running the engine near often enough to make a 6m change worth it. Modern synthetics are too good to break down and problematic at 6 months if it gets less than 1,000 miles of engine use on it at the 6 month change period. I'll change it at 12 months, even though the gas engine probably only has 1,500 miles of engine on time at that point. We got gas back in May and we've done 5,000kms since, with a third of a tank left still.
Thanks for the thought out response. I’ll be sure to take a few exits and pass a few people along the way, while coasting for some of it. It’s at 600 miles currently, so hopefully doing that for the few hundred more I’ll put on it during the trip back home will be sufficient. Now I just have to get done with the paperwork wait…
Oh, if it's already at 600 miles, then just drive as normal. The break in period is mostly the first 500 miles. An oil change when you get home wouldn't be the worst idea in the world, but it's totally up to you and your mindset. I personally believe strongly in 6m/5k, but obviously opinions vary. I strongly disagree with opinions like Zeromus's and I think the 6m interval becomes MORE important as the ICE does less work. At the very least, I wouldn't do 1y oil changes on a car like that without doing oil testing to see what the fuel contamination levels look like after 6m and 1y. And if you're doing the oil change yourself, the cost of the oil analysis is about the same as just doing the extra oil change. My reasoning(which I got from others vastly smarter than me with decades of experience): When an ICE sits for a length of time, the oil coating the cylinder walls will slowly leak down into the oil pan. The thinner oils like 0W-16 are even more prone to this(compared to 5W- or 10W- oils). When too much of the oil drips back down into the pan, the pistons can no longer seal properly at engine startup. Additionally, the engine computer sprays extra fuel into the cylinders during startup and for a couple minutes after. This creates a condition known as cylinder washdown. A good portion of the extra fuel leaks down into the oil pan, contaminating the fuel until the seal is reformed with new oil. Oil with fuel mixed in loses some of its lubricating ability, but the worse problem is that the fuel(which is a solvent) attacks the oil and any rubber seals it comes into contact with. As it attacks the oil, it breaks some of it down into the components that create sludge. In general, hybrids are more prone to this issue because they go through so many more engine starts versus a conventional car(thus more extra fuel - a.k.a. running rich). And hybrids that are used less, or PHEVs where the ICE can stay shut off for weeks at a time, are even more prone to it because they lose the oil seal in the cylinders more frequently. Additionally, hybrids in general, and PHEVs/very low milage HEVs in particular, often don't get their oil temp up high enough for long enough to boil out the fuel contamination. Thus, those owners should change their oil more often to keep the fuel contamination levels low and get rid of the damaged oil more frequently. Or at least that's my opinion. The three most important things to keep a Prius healthy beyond 150k: (you have to really screw up to get less than 150k) 1. 6m/5k oil changes 2. 5y/50k coolant changes (the Toyota pink coolant gets super acidic as it ages and attacks head gaskets and other parts) 3. (if HEV) Keep your HV battery cooling filter under the drivers side rear seat clean. (a clogged filter is the #1 cause by far of premature HV battery failure) Gen5 PHEVs use the A/C system to cool the HV battery, so those owners don't have to worry about the filter; though they do have to fix any A/C problems IMMEDIATELY. Transmission fluid changes around 7y/70k are also very good, but not nearly as important as the other three. Trust your manual for everything except things covered under ToyotaCare. Assume that Toyota cuts corners in those areas to keep the costs of the program down. Mainly talking about oil, coolant, and transmission fluid intervals. But feel free to take all of this with a grain of salt. It's your car(or it will be once the paperwork is done - lol).
I go very strict on the break-in procedure and do not exceed 55 mph and drive extremely gently for the first 1,000 miles according to the old-school break-in instructions. In general, the slower and more gently you drive in the fist 1,000 miles, you will have the longest-lasting and best-performing engine. I don’t believe in full throttle for break-in. I still don’t full-throttle to date. It seems to have worked. I am still getting 70–75 mpg at 45,000 miles. In other words, my car is better than new.
The oil that the factory put in the car. I doubt you will find "break in oil" of the correct viscosity anyway. If you did find it, you could void any Toyota engine warranty on the vehicle.
Those high-ZDDP-content break-in oils were for flat-tappet engines. With the precisely machined Japanese engines with roller lifters, all you need to do is to use the factory-fill oil that contains modern antiwear, extreme-pressure, and friction-modifier additives in its additive package and drive gently and avoid rapid acceleration and rapid braking and going much faster than 55 mph.
