JimWPB

It's my understanding that lockers & LSD are two different animals.

In my vocabulary, lockers solidly connect the axle shafts on both sides of the diff, with zero slip under all conditions. These can be "lunch box" lockers, that are permanently engaged, or other types of lockers can be engaged/disengaged with either air or electric switching. In the old days, before lunch box lockers were an off the shelf, bolt-in item that can be removed later, we would just weld the spider gears in place. It was a bit ghetto & it was not reversible, but it worked.

I have seen LSD come in 2 flavors. First, there is the traditional posi-traction style that has been around forever. This has a clutch inside the diff & often needs friction modifiers (posi-lube) in the gear oil to work well. These days there are also helical LSD systems that are basically pure gears with no clutch. I have no personal experience with the helicals, but I have read that in a situation where you have zero traction on one side, they may not send power to the other wheel. Apparently, they need a little drag to make them grab, but again, this is just what I have read.

greatwhitebuffalo

Most of what you said is spot-on; so-called 'lunchbox' lockers are not permanently engaged, however, they detect differences in wheel speed and will 'click' on and off to allow a turn under high traction conditions. pretty much everything else you said is correct, and yes, my LSD are not lockers. In the 'one wheel spinning in the air' scenario, an application of brake (or bld) should provide enough drag on the spinning wheel to get the helixes to bind. I do like that these truetracs require no maintenance and no friction modifier to work properly.

I think we all know that anything short of actual electronic or mechanical lockers with an on-off button is going to be less than controllable. But the rubicon ceased to be affordable a while ago, and a full locker install would then get a guy into a discussion of changing out the DANA 30, etc. If i had no BLD and no LSD, I suppose I'd be thinking about 'real' lockers. But in my short experience with these True-Tracs, I doubt I will ever need more. Thanks for your thoughts on this stuff.

JimWPB

Thanks for filling the hole in my knowledge base. After further research, I now see that the spline face coupling cogs in a lunch box are beveled on one side to allow them to free wheel ratchet in the forward direction. I had missed that detail before.

JimWPB

As was said before, different storms can produce different types of snow which can require different methods. The method you describe is often a good choice. Exceptions exist.

During the blizzard of 78 I was driving an old military 3/4-ton to get to a stuck snow plow. The snow on the road was over the height of the bumper. I spun the wheels until I dug down to raw pavement & got traction. I then pushed a pile of snow in front of me as far as I could go, then backed up, went around the pile & continued on until I pushed up another pile that was too big for me to move. I probably left about 30 piles behind me that the plow would need to clear after I got him going again. The nondirectional military treads on run-flat wheels would not float on top of, nor compact the snow enough to let me make progress any other way that I could think of that day. The snow was still coming down.

Sometimes it's better to stay on top of the snow. Sometimes it's better to dig down to what's under it.