Why balance the axel load?

Discussion in 'Questions From New Drivers' started by Lurchgs, Aug 24, 2008.

  1. Lurchgs

    Lurchgs Road Train Member

    2,122
    308
    Feb 13, 2008
    Denver, CO
    0
    This question came to me as I was reading the "weighing" thread here.

    From the outset, I've been told that - ideally - the weights on the drive tandem and the trailer tandems should be the same. What nobody's agreed on is *why*.

    The most common answer I've received is "Fuel mileage". On the face of it, that doesn't make sense (unless I'm missing something). Truck is still pulling the same weight, no matter how it's arranged.

    My personal inexpert thought is that it makes for safer braking - if the weights on the axels is the same, one set or the other is less likely to wander off track during heavy braking situations - making the articulated rig behave more like a straight truck.

    Anybody have a link to the facts and wherebys of this?
     
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. MGASSEL

    MGASSEL Road Train Member

    1,301
    211
    Mar 27, 2007
    Co
    0
    I belive that it has to do with traction too much weight on the tandems could possibly cause a jacknife when turning a corner.
    Making the drives skid because the weight of the trailer pushes you straight even though you are turning.
    It would be verry important try and be equal on your weights on dirt, gravel, wet roads, icy roads etc.

    I would agree about even braking when the weights are about the same but I belive that is more for the traction issues.
     
  4. jlkklj777

    jlkklj777 20 Year Truckload Veteran

    1,871
    1,090
    Oct 1, 2007
    Duncannon, Pa
    0
    During the winter time I will always place more weight on my drives rather than my trailer tandem. This helps with traction and in the case of hauling pups the lead trailer is always supposed to be the heavier of the 2.

    Having exactly the same weight on the drives and trailer tandem is not necessary (imo).
     
  5. lostNfound

    lostNfound Road Train Member

    3,506
    2,269
    Jun 28, 2007
    Home of the Stampede
    0
    You are missing something. (Now there's a loaded statement :biggrin_25525:)

    The truck is carrying the weight on the drives and dragging the weight on the trailer. Which is easier?

    Also, the deformation (and resulting rolling resistance) of the tire sidewalls has a significant effect on fuel mileage, hence the reason wide-base tires offer better fuel mileage. More highly loaded (and more deformed) tires have higher rolling resistance.

    Therefore, it does matter how the truck is loaded ... but not necessarily all that much in most cases.
     
  6. lyion

    lyion Light Load Member

    96
    5
    Feb 2, 2008
    TOANO VIRGINIA
    0
    i just read the answers drivers put on her for the question ,just to put my .02 in ,no one mentioned to much weight on the drives will ware you tires out ,in the sumer time if you have caps on the drives and run fast you can blow out them easy i fount this out the hard way a few year's go . also when you are trying to turn hard and if you go over a curb it may cause the trailer to dip down on to the tires and will gilge the tread then thos tires wontlast long and can blow out and it will make the ride ruff too. you will get your best ride with the fith wheel Al theway back but it will coast you in fuel milage ,your best fuel milage is as close as you can get the trailer to the back of the truck cab but most drivers company driver more so that dont haft to pay for the fuel like it all the way back for the ride.. sorry for getting some what off the subject.
     
  7. lyion

    lyion Light Load Member

    96
    5
    Feb 2, 2008
    TOANO VIRGINIA
    0
    hi, lyion here again. if you slide the fth wheel up, the closer you get to the back of the trucks cab the less wind resitance you get so by doing this you will get better fuel millage .34,000 on the trailer axles ,34,000 on the drives no more than 12,000 on the front axle thats the way it is .
     
  8. Working Class Patriot

    Working Class Patriot Road Train Member

    12,683
    23,165
    Jan 17, 2008
    Wherever and Whenever...
    0
    Sliding your fifth-wheel depends on your load, particularly if you have a flatbed. When I haul pipe that is over-length ( 60' or more), I have to slide it all the way back to allow for clearance behind the sleeper. Usually 2' is safe and that will leave around 10' overhang on the tail end which puts me at the legal limit in most western states except for CA which will let you go longer.

    I always try to get the trailer center loaded if possible and split the weight evenly as possible between the axles. I have a scale on the trailer and one on the tractor. Never had them on my dumps but as it happens, the day you go over 500 pounds on an axle set is the day you get nailed at the scale.
     
  9. Lurchgs

    Lurchgs Road Train Member

    2,122
    308
    Feb 13, 2008
    Denver, CO
    0
    Thanks folks...
    Hadn't considered tire deformation....

    Ron - yeah, that was part of my thought, really... the basic idea with traction is to do your best to make the entire rig behave (as best we can) like a straight truck. Mess with the weights,and things get wonky
     
  10. tinglish

    tinglish Light Load Member

    163
    52
    Aug 26, 2007
    Cottonwood, CA
    0
    when i worked for gordon, they had a large number of 3 axle trailers, legal to 42,000 on the trailer axles, so i ran alot with 32 on the drives and 36 on the trailer (and every other conceivable combination) all i cared was not getting tickets. they were licensed to 88,00 in or. wa. id. and utah (maybe montana too, don't remember.)

    now i pull doubles and if the road is dry, i put the heavy box in back if i'm over on the drive axle (single screw). i've pulled a 7,000 box with 24,000 on the back box, green light at the scale, and got where i was going in one piece. (just try not to look in the mirrors going through the canyon :) )
    i wouldn't do that if it was snowing though.
     
  11. MGASSEL

    MGASSEL Road Train Member

    1,301
    211
    Mar 27, 2007
    Co
    0
    I would go as much as 12300 -12500 on the steers but you have to be less than 34000 on the drives and less than 34000 on the tandems you can be over a little on any axle but you can not be more than 80000.
    The company rule book that I have says that.
    The truck you drive will dictate how and were you can put the weight.
     
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.