3 Way Locker Question

Let me try an explain the differential. Power comes in through the drive shaft that's turning say 400 rpm. Which turns the pinion gear which turns the bigger ring gear. If you had a ratio of 4:1 the ring gear would be turning 100 rpm no matter what it's a direct connection. Now the ring gear turns the axles but not through a direct connection. It uses a set of four spider gears 2of which are attached to the ring gear housing and the other 2 are attached to the axles, one each. That's the easy part. When the ring gear turns 100 rpm both axles are going to turn that same speed 100 rpm. Except when one tire loses traction the ring gear is still turning 100 rpm but now you have one tire turning faster than the other. That means if one side loses traction and is spinning 150 rpm the other side is turning 50. The wheel rpms will always be the same as the ring gears if you average them together.
I'm sure it could be said/written better but I think you'll get the idea.

 

No, you don't get it.

The answer to your question is that everything will be fine as long as your on terrain that will allow some wheel slip. Otherwise don't lock up a thing if you will be turning or you will bind things up and that could potentially lead to breakage. Your truck is working properly. All you are seeing is your front differential doing it's job and allowing differentiation. If your front drive tires all had equal traction then the one side would not be going any faster.

The working of the rear drive line can be difficult to visualize or explain. Once you get it you think " oh , of course ". It's just 3 differentials.

 

Yes, got it now. It was the difference in wheel speed that was driving me nuts. Thanks to everyone who tried to explain the principles involved.

 

FYI; I had a brand new 01 Star, 550 6nz, 18B, 46 rears @ 3.90, 11R24.5. My driver blew the rear drive shaft out from under the truck at 77,000mi. We were cutting pulp in VT on a dirt road that you had to chain up to get in and out because they dont believe in salt. The genius would just lock the divider and the last diff only. That sends all the power to the last drive with the small drive shaft. His reasoning was he thought it would steer better that way.

 

So it had full locks and he only used the rear, plus the power divider? Wouldn't that equate to the same thing I have, 3 way lockers? And would he not still have half the power going to one of the wheels on the front axle? When you say blew the rear drive shaft, could you be a bit more specific, did it break, or a yoke? Just trying to learn here, pulling super b's with 40's and 3 ways, not the best combo, but I drive her like I own her (which I do, hehe).

 

The yokes broke and threw the drive shaft out from under the truck. It probably only broke one first, then he didnt stop in time so blasted it out. Smoked the input, output yokes, and the anti-lock brake valve, with wires. Was fun on the side of RT100 in the cold to fix. My whole point is, the diffs should be ONE (1) switch. If you need to lock a diff, lock them both. My trucks only ran 110,000lbs, because thats whats legal in NY, VT is only 100,000lbs with 6 axles, but I kept them at 110,000lbs. So you have far more stress since you run B's. Its pretty safe to say you dont have mismatched rears. You would have seen huge problems by now.

 

So I can understand clearly, do you have 3 air switches? Divider, front diff, rear diff?

 

I have full lockers with 2 air switches in a pete, and then there are some KW with 3 switches and full lockers

 

Nope, just 2, one for the power divider and one for the locker in the rear diff. I wish it had a locker in the front diff, believe me, but I make the best of what she's got for now. At some point I may try to find a front one with a locker, we'll see.

 

Suspension design plays a huge roll in traction. What suspension do you run with the high weight that you carry? How many pusher axles on the truck?