AWD question

[(goldfish)]

There does seem to be some confusion to the vlsds. It's easiest to think of them kinda like an auto tranny. It takes some power to get it to transfer power, like an auto tranny's stall. If the Vlsd is designed right you will not overpower it.

[rweddy]

  (goldfish) said:

If the Vlsd is designed right you will not overpower it.

This is not true, you will always be able to overpower a LSD the only way to get a 50/50 split on an axle is with a true locking diff like a Detroit or an ARB.

[WoodsWagon]

Yes. the LSD's can get overpowered. Easily. They are better than open diff's because you can get out of situations where 2 wheels are slipping. How many have had one front wheel and one back wheel, on opposite corners, spinning? A LSD would help to get a bit of torque to the stationary wheel. It will not come near a 50/50 power split, only lockers or spools can do that. Since nobody makes lockers for us, and spools ruin streatability, the LSD is a second best solution thet lets us drive the cars on the pavement. Yeah, you get some torque steer when it gets slippery, but I'd rather that than being stuck. I've been in plenty of situations where a "light right foot" wouldn't get me out. A LSD in the rear would have.

[Setright]

Or maybe some more ground clearance?

[WoodsWagon]

You can do a lot without ground clearance if you have lockers or LSD's. The 4 runner has open diffs front and rear, but a transfer case in the middle, basically a spool instead of the viscious coupling that the newer subi's have. The older ones, like the 88 wagon mentioned have the same style transfer case as the 4-runner, its just built into the transaxle. Thus the 2 drive trains are fairly close, and the only difference between them is ground clearance. If the subi had a LSD in the rear, I'm willing to bet it would have made it through. I've been high centered plenty of times with good traction on 2 wheels, just not the others. If I had a LSD, I would have much better chances at making it off. Instead I have to jack up one corner and give traction to the other 2 wheels. Anyone doubting me, send me a LSD, and I'll install it in my wagon and show you the difference. I might not give it back afterward though.

[Scottbaru]

My VWs and Audis had locking rear diffs, and one of my Landcruisers had locking front, center, and rear. My brothers also all had quattros, and we had many hill climbing, deep snow, and ice competitions every winter. Locking the rear diff made a small but significant difference in many situations. Ground clearance, weight, and good tires usually helped the most in pushing snow. Locking the front diff helped a lot in traction, especially with the weight of the engine up there, but reduced steering authority.

 

 

Most of my lockers were disabled or couldn't be engaged over a certain speed. Things get dicey at normal road speeds with locked diffs, and even at slow speeds with the front locked. I only know of two passenger vehicles ever offered in the U.S. with a locking front diff: Landcruiser and Jeep Wrangler Rubicon. It's a liability thing. Limited slip diffs are just less locked, and can cause the same problems as locked diffs, in lesser degrees. I've never heard of a front LSD, doesn't sound like a good idea.