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OBDLink settings/what to monitor when towing long distances?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by flippo, Aug 2, 2022.

  1. flippo

    flippo Junior Member

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    I am going to take a long (9 hour) drive with my old Prius II, towing a U-haul trailer.

    What should I monitor on my ObdLink LX and android app, and what should I do if something looks out-of-tolerance? Pull over and let it cool down, switch to gear B?

    I have this device, but haven't used it much - only to scan for codes when something is wrong.

    I have towed with a Gen2 before, but never for this kind of distance. It is relatively flat land (Minneapolis to Indianapolis - gets a little hilly in Wisconsin). I'm guessing it will probably be just fine, but I want to stay on the cautious side and not get stranded.
     
  2. PriusCamper

    PriusCamper Senior Member

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    Main thing is having the ability to scan and clear codes while you drive... If you run into problems post your screenshots of error codes in this thread and we'll go over your options.
     
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  3. ydpplqbd

    ydpplqbd Active Member

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    When I tow, i monitor several things closely as follows:
    i.) outside temperature;
    ii.) trailer weight (trailer weighs roughly 10 times load on tongue);
    iii.) MG1 and MG2 temperatures;
    iv.) motor oil level;
    v.) severity of grades and length of grade;
    vi.) vehicle speed;
    vii.) coolant temperature; and
    viii.) charge level of battery.

    On very hot days (say over 90F), I try to avoid severe, long grades. On long, severe grades my goal is to NOT let the HV battery go below two bars. I would test out towing a loaded trailer up a couple long severe grades before setting out on an extended trip with trailer in tow. When i first started trailering, i quickly found out that my electric inverter coolant pump lacked sufficient flow for trailering. Solution, if you get inverter overheat is to let car cool down (and obviously fix the problem).

    PS make sure your brakes are in excellent shape. As most small trailers lack brakes. And, therefore you are depending on GEN2 brakes to stop the GEN2 and trailer.
     
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  4. PriusCamper

    PriusCamper Senior Member

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    How do you "monitor" trailer weight? And with a max tongue weight of 200 pounds, I suspect you're going to have a hard time keeping total trailer weight below 2000 pounds?

    Only thing I can think that you're leaving out is driving at night and avoiding the hills in Wisconsin during the hottest part of the day...
     
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  5. ydpplqbd

    ydpplqbd Active Member

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    I weigh the tongue weight with a bathroom scale and a piece of 4x4. I keep the trailer weight loaded to 2000 lbs or less. I have not had a problem with driving at night. And, during severely hot weather, i sometimes wait to leave until 9pm or 10pm in order to avoid excessive temperatures.
     
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  6. PriusCamper

    PriusCamper Senior Member

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    You're an excellent example of responsible trailer use with a Prius... I've never been forced to use a highway with my trailer and have been able to keep it below 45mph. I'd be very uncomfortable going faster because that much weight has too much influence over how a lightweight high MPG economy car handles.
     
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  7. ydpplqbd

    ydpplqbd Active Member

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    Thanks for the compliment.

    A whole other issue is weight distribution in the trailer and its effect on handling of the trailer and GEN2. Suffice to say, heaviest items should be placed over trailer axle (or slightly forward of trailer axle). Where trailer's center of gravity is behind the axle of trailer (IOW too much weight behind trailer axle) then I have experienced a pendulum effect (where trailer starts swaying excessively and continues swaying excessively)*. Lots of other issues in the same vein. Let me know if you want to discuss further.

    *- cure is to move heavy items forward enough to stop pendulum effect.
     
  8. flippo

    flippo Junior Member

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    Thanks all, I'll monitor the inverter temps. I've done that before when I had an inverter warning.

    Not too worried about the weight - I'm moving my kid from Uni and just barely need the trailer - it'll be mostly empty, and we'll tie everything down near the wheel wells so the trailer is taking most of the weight. The trunk area will be full. I've towed more weight using my Prius in the past without issue.
     
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  9. PriusCamper

    PriusCamper Senior Member

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    With a full load below 45mph the pendulum effect is felt, but it's just one sway or two and doesn't amplify/continue so not too concerned for my use, but maybe for you? They do make struts you add to your hitch rig to dampen that. So you might want to see if there's a cheap easy way to add something like that?

    For me, the real problem I'd like to address is the bouncing of the trailer on rough road is transferred to the hitch as as a push pull motion that relatively aggressively shakes the Prius, even at slow speeds. Does anyone know if there's a hitch stabilizing rig that would address that?

    I just did some research and found this device... I think I can use a spare pipe clamp from my aftermarket cat installs to eliminate lots of noise... But that doesn't address the push-pull which needs some kind of shock absorber built into the hitch receiver.

    58134_W8.jpg .
     
    #9 PriusCamper, Aug 3, 2022
    Last edited: Aug 3, 2022
  10. PriusCamper

    PriusCamper Senior Member

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    Basically, I'm looking for something like this that's not an antique that costs $100:

    s-l1600.jpg
     
  11. PriusCamper

    PriusCamper Senior Member

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  12. PriusCamper

    PriusCamper Senior Member

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