torque to the pavement
Postmaster
Joined: Dec 2002
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From: USA
Yes, you can calculate it mathematically and come up with a theoretical estimation of it. Alot of real-world factors wouldn't get factored in, but the result could be close enough. You'll have to search for the necessary equations to do it though...
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Senior User
Joined: Apr 2004
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From: NH
ok thanks. the reason i ask is because i have two military five tons and was told that they put some thing like 1500 foot lbs of tq to the pavement. 
this made me curios to see if there was a way to try to figure it out.
this made me curios to see if there was a way to try to figure it out.
Postmaster
Joined: Jul 2003
Posts: 2,711
Likes: 2
From: Pittsburgh
1500 lbs to the pavement really isn't that much.
My 300 puts out 250ish lbs of torque at the flywheel, i have a 1st gear of 6.32, and a rear end of 3.5 with 35" tires (17.5" radius)
SO, torqueXtotal gear reduction=torque to the axle
you then take torque to the axle divided by the decimal equivalent of a foot of the radius of your tire.
for me this is 17.5"/12" perfoot=1.4583 feet
(250x6.32x3.5)/1.4583= 3,792 lbs to the pavement
Then if I slip it into low range I get (250x6.32x2x3.5)/1.4583=7,584 lbs to the ground.
There ya go.
And on a side note, the greater the difference between torque to the axle and torque to the ground, the more likely you are to break an axle since the "lost" torque is trying to counteract the rotation of the tire.
See guys, now aren't you all happy that i paid attention in physics class
Justin
My 300 puts out 250ish lbs of torque at the flywheel, i have a 1st gear of 6.32, and a rear end of 3.5 with 35" tires (17.5" radius)
SO, torqueXtotal gear reduction=torque to the axle
you then take torque to the axle divided by the decimal equivalent of a foot of the radius of your tire.
for me this is 17.5"/12" perfoot=1.4583 feet
(250x6.32x3.5)/1.4583= 3,792 lbs to the pavement
Then if I slip it into low range I get (250x6.32x2x3.5)/1.4583=7,584 lbs to the ground.
There ya go.
And on a side note, the greater the difference between torque to the axle and torque to the ground, the more likely you are to break an axle since the "lost" torque is trying to counteract the rotation of the tire.
See guys, now aren't you all happy that i paid attention in physics class
Justin
Last edited by hoxiii; Jul 15, 2004 at 10:22 PM.
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From: NH
i'm trying to locate some of the specs for the trucks. all i have right now is the ring and pinion numbers rim size and motor numbers(hp and tq) what i don't have is the numbers for the tranny and the t case. does it make a difference that these trucks are all wheel drive?
Postmaster
Joined: Jul 2003
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From: Pittsburgh
Total torque to the pavement doesn't car if it's one wheel drive or 10,000 wheel drive, but torque per axle does.
When In 4 or 6 wheel drive (maybe on the 5 ton?) you divide the torque you're putting to the ground by the number of axles. So on a normal truck you'd take the total torque divided by two and each axle is recieving that amount with each wheel recieving half again as much. This is of course with equal traction.
So i 4lo when i'm putting 7,584 lbs to the ground that's actually 3,792 lbs per axle and 1,896 to each tire. BUT, If a tire spins and the other stops, that tire recieves the full 3,792 available pounds of torque. That's why it's "difficult" to break a tire loose, but once it goes it's gone.
IF you have a spool or locker in the axle, each tire will then recieve equal amounts of torque no matter what.
You're putting the same amount to the ground, just by several smaller paths instead of one large one.
Justin
When In 4 or 6 wheel drive (maybe on the 5 ton?) you divide the torque you're putting to the ground by the number of axles. So on a normal truck you'd take the total torque divided by two and each axle is recieving that amount with each wheel recieving half again as much. This is of course with equal traction.
So i 4lo when i'm putting 7,584 lbs to the ground that's actually 3,792 lbs per axle and 1,896 to each tire. BUT, If a tire spins and the other stops, that tire recieves the full 3,792 available pounds of torque. That's why it's "difficult" to break a tire loose, but once it goes it's gone.
IF you have a spool or locker in the axle, each tire will then recieve equal amounts of torque no matter what.
You're putting the same amount to the ground, just by several smaller paths instead of one large one.
Justin
