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Any engine/CVT problems driving above 85MPH in Prime?

Discussion in 'Prime Main Forum (2017-2022)' started by P.Neophyte, May 18, 2022.

  1. P.Neophyte

    P.Neophyte Junior Member

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    Unlike probably most Prime owners, I frequently drive over 88 MPH for 10-15 minutes, and frequently 80 MPH for miles. I have a 2020 XLE with 15K, so I'd like to hear the experience of owners with higher mileage and similar driving habits? Did the Prime take the speed without deleterious effects (other than fuel economy)?
    BTW, how fast have you ever gone in your Prime? How did it handle?
     
  2. john1701a

    john1701a Prius Guru

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    Nope, mine worked fine that fast while cruising through South Dakota and Wyoming many times.
     
  3. Washingtonian

    Washingtonian Senior Member

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    Took a trip from Seattle to Colorado and back a few months ago and in some parts the speed limit was 80. Set the cruise control to 90 and it did just fine. Probably affected the gas mileage a little. Averaged 44 mpg for the entire trip. Pretty inexpensive way to travel.
    Ray
     
  4. mistermojorizin

    mistermojorizin Active Member

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    I've driven 85-90 quite often. I'm around 65K miles so not really high mileage, but higher than some: It was fine. The fastest i've gone isabout 95mph. It's fine. crazy considering when I was young and drove sports cars i used to drive 130mph regulary and once hit over 160 on public roads. such a slow old man now.
     
  5. GregersonIT

    GregersonIT Member

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    Daily Driver at those speeds and I also only change the oil every 10-15k. no problems up till 120k so far. Still original brakes, looking to change secondary fluids this year.
     
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  6. Downrange

    Downrange Active Member

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    Well, factory tires suck above 90 mph. And the Prime seems to be "governed" to not exceed 105. Truly, it's a bit scary above 90. With some decent tires and the computer fixed, it should handle higher speeds, imo.
    I just completed a 2600 mile round trip, running 75-85 throughout. No problems.

    By the way, got 52 mpg that trip.
     
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  7. Downrange

    Downrange Active Member

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    sorry dupe post...
     
  8. GregersonIT

    GregersonIT Member

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    I've never gone 105 in the prime lol. But with defenders it seems to be pretty confident at 85-90. The factory tires really are scary in anything but ideal conditions without any pushing it. They just don't inspire a lick of confidence in the cars ability to handle. Upgraded tires, much much worth it. The only thing the factory tires were good for was really quite amazing fuel economy.
     
  9. shoreview

    shoreview Junior Member

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    I don't think I'd want to buy one used from you guys! But I understand, it's no fun to be bullied by oversized pickups on roads with effectively no speed enforcement.

    I'm curious if anyone has done a serious, large-sample study to graph out mpg for speed with the Prime.
     
  10. Trollbait

    Trollbait It's a D&D thing

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    Wayne Gerdes(xcel) at Cleanmpg does so for the cars he reviews, and actually owns a Prime, so there should be a graph there.
     
  11. PianoBench

    PianoBench Member

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    What is Toyota Hybrid System - YouTube

    MG1 (Generator) motor has a maximum output rating of 22.5 kW and helps propel the vehicle under certain conditions (31 HP and 29.5 ft-lbf max).

    MG2 (Motor) motor has a maximum output rating of 53 kW and can propel the vehicle on its own. (71 HP and 120.2 ft-lbf max) I believe that above a certain speed (maybe 65 to 70 MPH) the engine will kick in to aid MG2 to propel the vehicle down the road. But for speeds lower than 70 MPH, MG2 can propel the vehicle on its own.

    Both MG1 and MG2 have a rotational limit of 17000 RPM.


    I found only two speed ratings in the Toyota Manual for Prius Prime. First is under driving support systems PDF page 374. In that section, the maximum vehicle speed listed for the Pre-Collision system is 110 MPH. There is also another section on PDF page 311 that states not to drive the vehicle above 85 MPH unless the vehicle is equipped with high speed capable tires.

    I think this means that the eCVT motors+engine and vehicle safety electronics can handle the speed. But the factory OEM equipped tires cannot.

    Download toyota manuals from here. 2017 Toyota Prius Prime Manuals & Warranties | Toyota Owners

    The tires that come stock with the Prius (Toyo Nanoenergy) come with a speed rating of S or 112 MPH.

    For reference, the Rav4 Hybrid has an MG2 rated at 88kW (120HP) and maximum speed of 124 MPH for the motor itself.
     
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  12. douglasjre

    douglasjre Senior Member

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    What's wrong? Are you implying this does damage to the car?
     
  13. Dylan Morris

    Dylan Morris New Member

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    Your need a Mechanic;)
     
  14. GregersonIT

    GregersonIT Member

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    Mine has been pretty much a highway only baby. Granted I go longer between oil changes than factory recommended. But I still don't burn oil and I've been using nothing but higher quality stuff.
     
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