I guess that sometimes, when they guys like me and TTD who've been driving a few decades say things, it sounds like ancient history and tall tales. But here's a 5 yr driver running the roads through bad weather. And he's always trying to be productive...even in bad weather. He's hustling while sitting in his truck waiting. You don't think that people in the office don't notice. They notice. You're always ahead. It's not a big difference between the average driver and the top driver, it's a million little differences that puts you at the front of the pack.
Mr Lepton, I will drink my next adult beverage in your honor. Way to work it, driver. Salute!
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Yes, the power divider and the axle interlock ARE the same things (same, but just called by 2 different names)
But the "locker" is an entirely different animal, tho both the power divider/axle interlock and locker's main purposes is traction control.
The power divider (or axle interlock) couples (via 3rd "differential) the front tandem drive axle to the rear tandem drive axle.
The "locker" (if truck is equipped, as they are less common) locks the right side tires of the axle with the left side tires of that same axle.
The "locker" has no effect between the 2 separate axles, in itself. The locker only effects both sides of the SAME axle.
When the axle interlock is NOT engaged, power is provided to both rear drive axles, however differential action 'distributes' power in relation to path of lease resistance.
Whichever side of that axles loses traction, the power is lost thru that wheel, and that wheel spins.
When the axle interlock IS engaged, then the differential between the front & rear drive axles is then 'locked', and this provides torque to that additional 'shared' axle, but only to the point of least resistance (no traction on a wheel).
So that results in having one wheel on each axle to 'try' to provide power, provided you have friction. Again, if either wheel on each axle spins, all driving power is lost.
Now if you also have "locker axles", and engage those, then ALL 4 sets of duals will be powered.
(I won't get into differential power transfer as that's a whole science in itself)
EDIT/ADD: In the process of typing this, along with a "call of nature", it wasn't until after posting that I saw that TTR member "pullin trains" posted much of this same info a few posts back.Last edited: Feb 23, 2015
Where do people get the idea that power is only going to one wheel on the rear axle unless you have the power divider locked in?
With open diffs, power is sent to every corner equally, as long as traction at all 4 corners is sufficient. When there is NOT sufficient traction at all 4 corners, power flows through the path of least resistance. In other words, if the torque required to break traction is less than what is needed to move the truck, the wheel that can spin, will spin, and all power is sent to that spinning wheel. If you have an inter-axle lock (aka power divider), then the wheel with the least traction on each axle will spin once torque exceeds the available traction.
There is nothing in the driveline directing power to any particular corner of the rears, other than the power flowing through the path of least resistance...unless you have lockers engaged or limited slip differentials.Hammer166 Thanks this.
I used the term "mainly" for that reason. I mistakenly used the term "only" in one spot. I meant to say "mainly".
Rarely is there ever perfectly divided traction/resistance effects, so that power is 25% at each corner, correct?.
If power is always equally divided in most miles driven (under full traction conditions) as you say, then why do the right rear duals seem to always experience greater wear?
I'm not talking about just my truck, but all trucks.
Another question,, seriously. If the front & rear drive axles share power at all times, then why the need to activate a power divider function, via switch?
I'm trying to learn, since you seem knowledgeable in this, what actually "changes" between power divider activation & non-activation.
I hate to get too off topic with the original/main intent of TripleSix's thread, tho the use & operation of the power divider is "weather/traction" related.Last edited: Feb 23, 2015
I see alot of bad advice being given on using the power divider. It's OK to leave the power divider in at highways speeds. Up here in Canada for the winter months we put the power divider in at the beginning of winter and don't take it out till spring break up. I've never seen a rear end burn up from having the power divider engaged all the time.
Never engage the power divider or lockers when the wheels are spinning.
Scroll down to the "loss of traction" part...explains it pretty well without taking up a ton of space here:
As far as power dividers go, ALL that does is lock the inter-axle differential so that power is sent to both drive axles. With that differential left "open", torque applied to ALL 4 wheel ends is limited by the traction available to the 1 wheel end with the LEAST traction available. Lock it in, and the torque applied to all 4 wheel ends is limited to the traction available on the 2 wheel ends (one on each axle) with the least traction. In other words, with it unlocked you are guaranteed to have at least 1 wheel spinning. Lock it, and you'll have at least 2 wheels (one on each axle) spinning.
the power divider on most trucks is on the front axle. the rear axle has no power applied to it whatsoever until the power divider is locked in. when you lock in the power divider an air piston engages a gear which then transmits power thru a drive shaft connected to the rear axle. so if your power divider is unlocked, your rear axle is receiving no more torque than the steer axle. if that makes any sense...
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