Page 1 of 4 123 ... LastLast
Results 1 to 10 of 33

Thread: MT engine wear fear (concerned about high engine RPM at highway speeds)

  1. #1
    Member TFCfan2021's Avatar
    Join Date
    Nov 2015
    Location
    Pittsburgh, PA
    Country
    United States
    Posts
    45
    Thanks
    1
    Thanked 4 Times in 3 Posts

    MT engine wear fear (concerned about high engine RPM at highway speeds)

    Am I the only one worried that my 2015 MT engine running at nearly 3,000 rpm at 60 mph for extended highway runs is going to cause premature engine wear vs a CVT model? I intend to drive this vehicle until failure.

    I have been keeping highway speeds down to 55mph just to help reduce the rpms a tad bit. I'm not really in a hurry to get anywhere and if I could slow down more without being ran over on the highway I would. Here in PA most 4 lane highway speed limits are 55 mph, most folks do 70 or more with no second thought.

    I guess it's just me, but I would hope the folks at Mitsubishi made this engine to run at those rpms. I just see in my mind piston rings screaming for help.

    Can anyone help calm my fears? Am I the only one? This may be partially due to being a big motor guy owning his first small motor car?



  2. #2
    Moderator inuvik's Avatar
    Join Date
    May 2015
    Location
    Coos Bay, OR
    Country
    United States
    Posts
    2,889
    Thanks
    2,371
    Thanked 1,075 Times in 781 Posts
    Quote Originally Posted by TFCfan2021 View Post
    Am I the only one worried that my 2015 MT engine running at nearly 3,000 rpm at 60 mph for extended highway runs is going to cause premature engine wear vs a CVT model? I intend to drive this vehicle until failure.

    I have been keeping highway speeds down to 55mph just to help reduce the rpms a tad bit. I'm not really in a hurry to get anywhere and if I could slow down more without being ran over on the highway I would. Here in PA most 4 lane highway speed limits are 55 mph, most folks do 70 or more with no second thought.

    I guess it's just me, but I would hope the folks at Mitsubishi made this engine to run at those rpms. I just see in my mind piston rings screaming for help.

    Can anyone help calm my fears? Am I the only one? This may be partially due to being a big motor guy owning his first small motor car?
    I think you can relax. I had a 1987 Dodge Colt with a 4 speed than turned 3500rpm at 60 mph. I sold it with over 200k miles. Still didn't burn any oil. Mitsubishi makes a excellent small motor. With a double over head cam multi-valve engine you shouldn't worry. You should be able to run this motor continously at these rpm's without fear of shortening the lifespan of the motor.

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 automatic: 40.4 mpg (US) ... 17.2 km/L ... 5.8 L/100 km ... 48.5 mpg (Imp)


  3. #3
    Member TFCfan2021's Avatar
    Join Date
    Nov 2015
    Location
    Pittsburgh, PA
    Country
    United States
    Posts
    45
    Thanks
    1
    Thanked 4 Times in 3 Posts
    I sure hope you are right...

  4. #4
    Senior Member laceygirl's Avatar
    Join Date
    Jul 2015
    Location
    Canberra Australia
    Country
    Australia
    Posts
    645
    Thanks
    378
    Thanked 119 Times in 101 Posts
    At 120 kilometres an hour my manual mirage is pulling about 3200 revs on the taco.... It loves it...

        __________________________________________

        click to view fuel log View my fuel log 2014 Mirage LS 1.2 manual: 38.0 mpg (US) ... 16.2 km/L ... 6.2 L/100 km ... 45.7 mpg (Imp)


  5. #5
    Senior Member
    Join Date
    May 2014
    Location
    Minnesota
    Country
    United States
    Posts
    160
    Garage empty: add car
    Thanks
    6
    Thanked 25 Times in 18 Posts
    Most motorcycles engines are spinning at 5,000+RPM at 60MPH.

    A friend of mine had a VW jetta that spun at 3K on the highway, he sold it with over 350,000 miles on it.

    I wouldn't worry about it.

  6. #6
    Member TFCfan2021's Avatar
    Join Date
    Nov 2015
    Location
    Pittsburgh, PA
    Country
    United States
    Posts
    45
    Thanks
    1
    Thanked 4 Times in 3 Posts
    Granted, this motor is smaller than most motorcycles... but...

    For the sake of argument, isn't there something to be said about the higher rpms vs it's CVT counterpart? More movement and faster movement means more heat, more friction, more wear, etc?

  7. #7
    Moderator inuvik's Avatar
    Join Date
    May 2015
    Location
    Coos Bay, OR
    Country
    United States
    Posts
    2,889
    Thanks
    2,371
    Thanked 1,075 Times in 781 Posts
    Quote Originally Posted by TFCfan2021 View Post
    I sure hope you are right...
    You don't have to worry about blowing a timing belt because the Mirage has a timing chain. Torque peak on the 3A92 is 4200 rpm so I wouldn't be worried about humming along between 3-4k rpm. In fact it's probably harder on the engine to lug around like the CVT likes to do. That's why I've never worried about when crusing at 60 mph coming up to a hill and the CVT will rev up to 4800-5000 before dropping down to between 3000-3500 rpm to climb a grade. Let 'er rev !!!

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 automatic: 40.4 mpg (US) ... 17.2 km/L ... 5.8 L/100 km ... 48.5 mpg (Imp)


  8. The Following User Says Thank You to inuvik For This Useful Post:

    laceygirl (11-06-2015)

  9. #8
    Moderator
    Join Date
    Jul 2015
    Location
    Mitsu
    Country
    United States
    Posts
    1,359
    Garage empty: add car
    Thanks
    256
    Thanked 314 Times in 245 Posts
    I wouldn't worry as log as you use quality synthetic oil. The car we traded in for Mirage, 1996 Protege with 1.5L engine was geared the same 3,000RPM at 60mph. It had 433,740mi on odometer, engine has never been rebuilt. Most of wear happens during cold start, so it is important to baby it 1st 5-10min.
    Last edited by cyclopathic; 11-06-2015 at 01:02 PM.

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage DE 1.2 manual: 46.4 mpg (US) ... 19.7 km/L ... 5.1 L/100 km ... 55.7 mpg (Imp)


  10. #9
    Senior Member Cobrajet's Avatar
    Join Date
    May 2015
    Location
    Olympia, WA
    Country
    United States
    Posts
    2,538
    Thanks
    950
    Thanked 1,409 Times in 857 Posts
    I'd wager that 3000 rpm, while high for an old 350 Chevy, isn't much for a small modern motor. Especially one that redlines at 6500 rpm.

    Keep the oil clean and I wouldn't worry too much about it.

  11. #10
    Senior Member
    Join Date
    May 2014
    Location
    Central NY
    Country
    United States
    Posts
    351
    Thanks
    0
    Thanked 19 Times in 17 Posts
    Quote Originally Posted by Cobrajet View Post
    I'd wager that 3000 rpm, while high for an old 350 Chevy, isn't much for a small modern motor. Especially one that redlines at 6500 rpm.

    Keep the oil clean and I wouldn't worry too much about it.
    My old Jeep 4.0 had no problem running at 3700 RPM for 70 miles towing in 2nd gear at 65MPH!

    The 3A92 has a LONGER stroke than a 350 small block! If a 350 can run all day at 3000RPM - and they did in dump trucks - the Mitsubishi engine will have no problem!

    Also - most modern engines don't have piston skirts. The only thing I would be worried about in a modern engine for high RPM operation would be the long cam chain for running the dual overhead cams. Even at that - the only companies that seem to have issues with cam chains is VW and GM so you're safe!


    Last edited by M-88; 11-06-2015 at 01:42 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •