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Hitch Bracing to increase tongue weight for Cargo Carrier

Discussion in 'Gen 3 Prius Accessories and Modifications' started by mp3_e46, Jan 13, 2013.

  1. mp3_e46

    mp3_e46 Junior Member

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    A few threads semi-covered this but searching showed no definitive answer.

    Has anyone used a hitched mounted cargo carrier for a while with success? Do we know what a reasonable tongue weight is?

    Likely I'll build a brace but didn't see anywhere obvious to mount it to. The yellow area in the picture would be easiest but it does not look strong. Since it's a decent distance back from the hitch that's probably ok.

    It's a while since I installed the hitch. Does anyone know if there is anywhere to secure near the green area? Blue are the only current mounting points; possibly we could add bracing above these to extend the contact area?


    [​IMG]
     
  2. ForestBeekeeper

    ForestBeekeeper Active Member

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    I am not sure if we should be increasing tongue weight.
     
  3. PriusCamper

    PriusCamper Senior Member

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    I'd agree if we're talking 70 mph on a freeway, but if it's safely slowly driving on rural forest roads with beehives in tow I think ForestBeekeper is being prudent & responsible to want a little more reinforcement...

    I suggest designing something that reinforces the cargo carrier from above, perhaps get a bike rack that's designed for a Prius and then add some straps so it can carry/stabilize the load.

    And if you really want to get into it you can design the structure as a boat tail to improve aerodynamics. A well designed boat tail is the #1 to improve MPG... It can increase MPG by 15%.

    Learn more here: Aerodynamic tail makes Geo Metro even cooler
     

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  4. xliderider

    xliderider Senior Member

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    Agreed, the OP didn't say how much weight they wanted to handle in the hitch mounted carrier. Perhaps the OP should be looking into a small trailer? Less stress on the Prius' rear suspension components, more load capacity, no modifications needed, etc.
     
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  5. PriusCamper

    PriusCamper Senior Member

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    It's obvious the weight for the hitch mounted carrier is going to be close to the limit because the original poster's name is Forest Beekeper. I mean everyone knows the basic size of a commercial beehive don't they?
     
  6. xliderider

    xliderider Senior Member

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    Sorry, but the OP was not Forrest Beekeeper. ;)
     
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  7. ForestBeekeeper

    ForestBeekeeper Active Member

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    I am not the OP, however I think that a standard beehive loaded with honey would far exceed how much weight can be safely added onto the rear of a Prius. No, make that an extended 2 foot beyond the rear of a Prius. :)

    On occasion, I load my truck down now, to where the front tires have so little weight on them that those front tires begin to lose steerage ability. I would hate to see that on a Prius. :)
     
  8. mp3_e46

    mp3_e46 Junior Member

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    It's for something like this:

    [​IMG]

    Without the dog; but with a large tent and mattress topper. Will be used for a coast to coast month long trip; hoping not to need a roof box or trailer

    Some apparently use these cargo carriers ok but I'd rather be safe and add bracing. Would love to hear from anyone who's loaded 100+ lbs and used such a cargo carrier extensively at 80+ mph highway speeds
     
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  9. ForestBeekeeper

    ForestBeekeeper Active Member

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    You don't like dogs?

    :)
     
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  10. mrstop

    mrstop PWR Mode

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  11. ForestBeekeeper

    ForestBeekeeper Active Member

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    This thread seems to be about increasing tongue weight from 200 up to something more. 500?

    I have a couple trailers, 500 pound tongue weight is not uncommon.

    I would be cautious about adding much weight on a lever hanging out the back of a Prius, as it might effect handling and therefore safety.

    Trust me, I hate consuming 6 to 8 gallons of gas for every mile that I drive my truck to haul things. I would love to throw a trailer on the back of a Prius. But I am concerned about safety. :)
     
  12. peterjmc

    peterjmc Ping pong in Ding Dang...

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    The yellow area identified in your picture is the rear lift point for a floor jack. I think that area is fairly strong :)
     
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  13. mp3_e46

    mp3_e46 Junior Member

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    Oh, a useful reply :) Thanks greatly, a quick Google agrees. I'll did out the manual this evening to reassure myself and get a brace built. Thanks again!

    Likely it's ok without a brace but I am hanging ~200lbs off the back of a 'flimsy' car and driving coast-to-coast so better to be safe than sorry. I've read too many stories of car mounted hitches bending due to overloading with just bicycles. Most prevelant issue is people covering the bikes with a tarp then doing 90 mph+ on the highway
     
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  14. PriusCamper

    PriusCamper Senior Member

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    A car bouncing down a highway at speed will put all kinds of never-ending variations of load and vibration on those mounts. Reinforcement makes sense even with a light load if you're traveling a long distance.

    But I still say reinforce from above with straps attached to the hatch down to the corners of the rack.. (same way they mount with bike racks) You'll experience less road hazards / damage to your rigging that way...
     
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  15. mp3_e46

    mp3_e46 Junior Member

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    After thinking about this for a while I am pretty sure I'll drill up into the boot if possible; one or two bolts with long steel plate above should be overkill. Don't want to have the mount bend on us 3,000 miles from home!

    Straps to the rack are a good idea but I'd like something we can't say "oh we'll be ok without them for this short trip"
     
  16. PriusCamper

    PriusCamper Senior Member

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    Yes, but it's always good to have an extra set of straps to use for a bumpy road or when you're forced to carry a load that's heavier than you anticipated... As someone who has seen people lose a load in front of me at freeway speed because they didn't tie it down enough: I think it's really important to overdue it when tying down a load.
     
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  17. mp3_e46

    mp3_e46 Junior Member

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    Agree. Have been using these straps since '99 and have four sets now (different lengths): Amazon.com: Thule Load Strap - 2 Pack: Sports & Outdoors

    Great, especially when towing my Hazzard Frought utility trailer. This year I've used over 110 sheets of 8x4 drywall remodelling our latest house - all transported on that ~$200 trailer (not all at once though!). It's amusing to see people at the Home Depot struggle with loading $40K+ pickups etc while they gawp at my Prius and trailer being a breeze to load more than they bought :)
     

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