I know what you said. It's false.

I have a feeling this won't involve any real science, but let's see...

Wow, this is actually true! Maybe we're getting somewhere.

The tires in the air will spin. The tires on the ground with traction will not. This is why they make lockers btw.

Here's where it all goes downhill...and fast. Did you ever stop to think what happens to the 2 tires in the air when you apply the brakes??? Those 2 tires receive the same amount of additional braking friction as the 2 on the ground. You're not adding friction to just the 2 tires, you're adding it to all 4 evenly. If there wasn't enough torque to make them spin before applying the brakes, then applying equal friction to all 4 tires isn't changing anything!

Now, I'm not saying that brake modulation won't help some, but let's be realistic here. By pumping the brakes and giving it a ton of throttle you can usually get the tires with traction to break free and rotate maybe a 1/2 - 1 complete revolution. Saying all 4 tires will magically start spinning at the same speed is just plain false. Anyone who's been stuck in that same situation know's the truth. Anyone who 'wheels hard also knows that LSD's are completley useless when tires are off the ground.

Not complicated at all. Anyone who 'wheels hard knows the true limitations of a LSD. Wanna keep digging???

 

Your example of being crossed up in a ditch won't work with an open diff and here's why: An open diff always applies equal torque to each wheel. If you brake torque with one wheel off the ground it won't help because one wheel will spin easier than the other. The hanging wheel will spin easier and the added brake friction is equal. So the hanging wheel will spin with the brake on and the wheel with traction will not spin because the brake resistance is the same but the traction remains different. It's the same condition as before the brake was applied. If you could apply the brake only to the hanging wheel you could drive right out, but applying equal brake force doesn't help. An open diff always applies equal torque, but not equal speed.

Wetspirit

 

That is to say, that is: "Docendo disco, scribendo cogito"

 

You are way too smart! In fact, I only know what 3 of those words mean. I know "To instruct, to learn, to think" but what the hell is scribendo?!?!?!

 

It turns out that after all this time. After all the designing of differentials, the selling and installing. All the poor souls that got stuck. All the cost and debating. Well, it turns out all that was needed with an open diff was to step on the brake pedal! Wow! Why didn't I think of that?! Next time I'm rock crawling, or a wheel is hangng in the air I'll give that a try, if I can remember it. I love scientific solutions.




Wetspirit

 

53 ******,

When I purchased my truck there was an extra charge for the "anti spin" diff marked clearly on the window sticker and build sheet. Nowhere did it say "limited slip".

I believe that they are two different things entirely, hence all the confusion.

Rick

 

No - they're just different terms for the traction aids in the differentials.

The window stickers for my '98 (Dana 80) and my '05 (AAM) both say "anti-spin"....

 

Not really, D - but in the vernacular, "I learn by teaching, think by writing"

 

That was the problem; not knowing the third word, I could not assmble the sentence unlike "cogito ergo sum" where the literal translation actually makes the phrase. That has to be Plato I would imagine because even though that sounds like Socrates, Socrates never wrote anything down, only Plato. I suppose it could be Arostotile, but my bets are on Plato.

Good phrase by the way!

 

Correct.

Point being:

If it does not say "anti spin.......$300.00" on the build sheet then you do not have a "limited slip".

It is a markable option on the J build trucks and standard equipment on the H build trucks. If you don't read every option on the list you could very easily get a truck that does not have the "anti spin" limited slip.

Rick

 

D - it certainly wasn't the semi-literate Socrates, but I don't recall either Plato or Aristotle getting credit for that nugget.... besides, anything they had to say was Greek - and Roman grammarians and Muslim scholars translated what little of their works survived centuries after their deaths.

It's merely one of the expressions from back in the day...

 

Blah blah blah blah blah
this thread sucks
and I have been to busy to look at my truck today.
I didn't ask the difference between lockers and limited slip so lets quit arguing about it.

 

Rick My sticker does have it...."Anti-Spin Differential Axle".......$285

the part that's disappointing is the 01 limited slip that every one "hates" was awesome IMHO If I stop at the bottom of my drive way with the 01 I could give it regular amount of go pedal and BOTH tires would lock up and drive me straight up the drive way.
I never had to milk it, Gas it or apply brakes to get it to work

 

I bet 100 bucks your diff is empty.

Your diff got stiffed!

 

I am going to get in trouble for this...

but,

JRussel, you are not the brightest light out there.

You are still arguing apples to oranges. Everything I said about getting four tires to spin is true. I wheel hard...and have been forced to do this before.

I am sorry if you disagree. So if I can prove it mathmatically...and in the real world, why do you argue?

I have still yet to say that a open or LSD diff as good as a locker. I have simpley described a method to make 4 wheels turn the same speed.

Email me to carry this on further not at the expense of other DTR members.

cquestad@ssproducts.com

Christian Questad, PE

Back on topic...I still wager the diff is empty if it is performing that poorly.

Back to the topic