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oxygen's avatar
oxygen
Explorer II
Jul 08, 2013

Help with scale numbers

Weighed at local grain elevator and here are the numbers

truck by itself
steer axle-3240lbs
drive axle-3000
gross weight-6240

tt + tv- WDH(equalizer) bars disconnected

steer axle- 2940
drive axle- 4200
trailer axle - 5360lbs.
gross weight- 12500

tt + tv-WDH engaged

steer axle- 3060
drive axle- 3900
trailer axle- 5540
gross weight- 12500

tv is Rockwood Ultra Lite, ship weight- 5676, hitch weight- 739
gvwr- 6739, this info taken from web site, yellow sticker on side of tv for dry weight is 5840lbs

tv iv 2012 f150 EB, screw, heavy duty, payload is 2440lbs.

please ?check my math

total gross weight mlnus truck gross, engaged = trailer weight = 5540lbs

tv engaged Wdh minus tv unhitched = 720lbs , weight transfered to tv

tt hitched axle weight minus tt unhitched axle weight = 180lbs.

720lbs. + 180lbs. = 9oolb tongue weight

tongue weight is 16% of tt weight

front axle tv unhitched minus hitched front axle = 300lbs.

engaging wdh put back 180lbs to steer axle

is tongue weight added to tt axle weight to get tt weight?

any adjustments needed?






any adjustments i should make to wdh?
  • Ron_Gratz's avatar
    Ron_Gratz
    Explorer
    Jul 10, 2013
    oxygen wrote:
    I just took scale weights, left the DW and dog out of the picture
    Okay, let's take the scale numbers and make an adjustment for the WDH which was not included in the "T only" values.
    We'll assume the WDH would remove 40# from the front axle and add 140# to the rear axle.

    The "adjusted" weights for TV only are
    Front = 3240-40 = 3200#, Rear = 3000+140 = 3140#, TV GVW = 6340#.

    For TV+TT w/ no WD, Front = 2940#, Rear = 4200#, TT axles = 5360#

    The indicated tongue weight is (2940+4200)-(3200+3140) = 800#.
    The indicated total TT weight is 12500-6340= 6160#.
    The indicated tongue weight percentage = 800/6160 = 13%.

    The indicated load removed from the front axle is 3200-2940 = 260#.
    With an 800# TW, I would expect closer to 340# removed.

    For TV+TT w/ WD, Front = 3060#, Rear = 3900#, TT axles = 5540#.

    The indicated load added to the TT axles by WD is 5540-5360 = 180#.
    The indicated load added to the TV's front axle by WD is 3060-2940 = 120#.
    It is physically impossible for your rig to have 180# transferred to the TT axles, while having only 120# transferred to the TV's front axle.
    The amount transferred to the front axle should be close to 340#.

    The indicated load removed from the rear is 4200-3900 = 300#.
    The amount removed from the rear should be close to 520#.

    After accounting for the WDH not being included in the "TV only" weights, the indicated tongue weight now is 800#.
    However, based on what you've reported there, there still is a discrepancy between the expected load removal from the front axle.
    And, there still is a significant discrepancy between the hitched with WD and hitched without WD values.

    BTW -- your first post says the GCW is 12,500#. The latest post says the GCW is 12,300#. Which is correct? My analysis above assumes the GCW is 12,500#.

    Ron
  • oxygen's avatar
    oxygen
    Explorer II
    Jul 10, 2013
    Ron Gratz wrote:
    oxygen wrote:
    truck by itsef, no wdh attachd, i was sitting in truck with all 3 weight

    front axle-3240
    gross tv- 6040
    fear axle- 3000, calculated from fist two

    truck hitched but bars NOT engaged

    front axle- 2940
    tt & tv- 12300
    trailer -5360
    rear axle- 4200, calculated

    truck hitch, wdh engaged

    front axle- 3060
    gross weigh- 12300
    trailer- 5540
    rear axle- 3900, calculated
    Where did you add the 200# for DW + dog?


    I just took scale weights, left the DW and dog out of the picture
  • Ron_Gratz's avatar
    Ron_Gratz
    Explorer
    Jul 10, 2013
    oxygen wrote:
    truck by itsef, no wdh attachd, i was sitting in truck with all 3 weight

    front axle-3240
    gross tv- 6040
    fear axle- 3000, calculated from fist two

    truck hitched but bars NOT engaged

    front axle- 2940
    tt & tv- 12300
    trailer -5360
    rear axle- 4200, calculated

    truck hitch, wdh engaged

    front axle- 3060
    gross weigh- 12300
    trailer- 5540
    rear axle- 3900, calculated
    Where did you add the 200# for DW + dog?
  • Ron_Gratz's avatar
    Ron_Gratz
    Explorer
    Jul 10, 2013
    oxygen wrote:
    1. is wdh to be attached when weighing only truck? I had it removed.
    IMO, the WDH should be in the receiver and the bars should be in the WDH when all weighing is done.

    2. tt + tv, wdh not engaged, i left the bars hanging inhead socket..should they have been put into tt?
    It's best to leave the bars hanging in the sockets.

    is wdhand bars considered part of tt or tv or combination of both when it comes to weight numbers?
    Strictly speaking -- the shank and ball mount should be considered part of the TV and the bars should be considered part of the TT.
    However, I think it's easier, and sufficient, to treat the entire WDH as part of the TV.

    Ron
  • oxygen's avatar
    oxygen
    Explorer II
    Jul 10, 2013
    Ron Gratz wrote:
    oxygen wrote:
    ---I likely messed up when I added 200lbs for Dw and our dog(who weighs 60lbs) to the gross weights because they weren't present for weighing.

    Also note that rear axle on tv was a calculated value from other weights listed.
    I subtracted steer axle unhitched from steer axle with wdh disconnected to get the 300lbs. Is this correct?

    Can you post the actual scales numbers?

    Also would help to know if you were in the cab, on the scales, or not included in any of the scale weights.

    Ron


    truck by itsef, no wdh attachd, i was sitting in truck with all 3 weight

    front axle-3240
    gross tv- 6040
    fear axle- 3000, calculated from fist two

    truck hitched but bars NOT engaged

    front axle- 2940
    tt & tv- 12300
    trailer -5360
    rear axle- 4200, calculated

    truck hitch, wdh engaged

    front axle- 3060
    gross weigh- 12300
    trailer- 5540
    rear axle- 3900, calculated
  • Ron_Gratz's avatar
    Ron_Gratz
    Explorer
    Jul 10, 2013
    oxygen wrote:
    ---I likely messed up when I added 200lbs for Dw and our dog(who weighs 60lbs) to the gross weights because they weren't present for weighing.

    Also note that rear axle on tv was a calculated value from other weights listed.
    I subtracted steer axle unhitched from steer axle with wdh disconnected to get the 300lbs. Is this correct?

    Can you post the actual scales numbers?

    Also would help to know if you were in the cab, on the scales, or not included in any of the scale weights.

    Ron
  • oxygen's avatar
    oxygen
    Explorer II
    Jul 10, 2013
    2 other questions

    1. is wdh to be attached when weighing only truck? I had it removed.

    2. tt + tv, wdh not engaged, i left the bars hanging inhead socket..should they have been put into tt?

    is wdhand bars considered part of tt or tv or combination of both when it comes to weight numbers?

    didn't weight wd by itself, but guess it weighs appr. 100 lbs or so
  • oxygen's avatar
    oxygen
    Explorer II
    Jul 10, 2013
    Sorry about messing up with quoted portion of Rons question.
  • oxygen's avatar
    oxygen
    Explorer II
    Jul 10, 2013
    Ron Gratz wrote:
    oxygen,

    There is a discrepancy in your data.

    It appears that approximately 220# was moved from the steer axle pad and added to the drive axle pad prior to making the "tt + tv-WDH engaged" weighing.

    If so, that would mean your WDH caused 340# to be added to the steer axle -- versus the indicated 300# removed when tongue weight was applied with no WD.
    This would mean your WDH was adjusted to transfer too much load.

    Is your weight any where near 220#, and is it possible that you moved from the steer axle pad to the drive axle pad prior to making that
    weighing?

    Ron, thanks for joining the discussion. I always enjoy your posts. I likely messed up when I added 200lbs for Dw and our dog(who weighs 60lbs) to the gross weights because they weren't present for weighing.

    Also note that rear axle on tv was a calculated value from other weights listed.
    I subtracted steer axle unhitched from steer axle with wdh disconnected to get the 300lbs. Is this correct?

    Any help with tese numbers would be very appreciated. The more I work with the numbers, the less sure I become.

    Ron
  • Ron_Gratz's avatar
    Ron_Gratz
    Explorer
    Jul 10, 2013
    oxygen,

    There is a discrepancy in your data.

    It appears that approximately 220# was moved from the steer axle pad and added to the drive axle pad prior to making the "tt + tv-WDH engaged" weighing.

    If so, that would mean your WDH caused 340# to be added to the steer axle -- versus the indicated 300# removed when tongue weight was applied with no WD.
    This would mean your WDH was adjusted to transfer too much load.

    Is your weight any where near 220#, and is it possible that you moved from the steer axle pad to the drive axle pad prior to making that weighing?

    Ron

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