What?? No no Troy just told me he was gonna get it a month ago. But we kinda had to do his cat this month. We are looking at just buying the whole regeared andl ockered 3rd member assembly. But it is $$ so it will be at least another month. Don't worry I will have it in time to wheel with ya.

 

Ahhh...Hmmmm, Troy's cat vs your frond diff...Yeah, not really seeing your logic on that one...

Talk to Adrian before you do that...He got a fully set up diff from the west coast (i believe) and had it crap teeth on the 5.29's. Something to check into at least.

 

I'd say you all qualify as experts...




















...expert smartasses.

 

When there is more weight on the rear, you have a greater "traction force."

Here's the principle at work:
Given: You are climbing a slippery hill under throttle.
(A) Locker is in the front, rear is open: if you lose traction and spin a tire in the front, you are okay. If you lose traction on a wheel in the rear, you spin, suddenly the two front tires will take all of the load, and since they have less "traction force" they are very likely to both begin to spin.

(B) Open front, locker in the rear: If you lose traction in the front, the rear is still pushing you and you're okay. If you lose traction in the back, you have a locker and you will still have one tire pushing with plenty of traction force and the front can make up for the traction-less tire in the rear.

Take a statics course and then think about that again

 

I think a Dynamics course would be more beneficial since we are dealing with motion.

 

fecal dynamics?

 

Instead of arguing about something as simple as this... why not take a vehicle with selectables front and rear and go run a bunch of obstances back to back with each combo and see what situations each one excels at?

You could make a nice report with pictures and everything and become an internet legend

 

Yeah...

So this has gotten severely of topic and out of hand. Folks, we don't really need to be debating experience or toyota trueness, or any of that other stuff.

The main issue is this: NO ONE is wrong. Got it? NO ONE. You all have valid experience, and giving that experience is what the poster of this thread needed.

Is a rear better? Sure, in some situations, several have been listed.

Is a front better? Sure, in some situations. I myself run only a front locker. It has, in several situations, gotten me through obstacles that extremely similar, rear locked only trucks, did not get up.

In the end, its probably equal. On a steep slipery climb, sure, the rear is probably better. On a slickrock ledge where the rear sits in sand, the front is probably better. For the rest of the time, its probably a wash. Either way, for the majority of lifted tires on most trails, either one is going to keep you moving forward, and that is what counts.

Now, Cargun has hit the nail on the head. The only way to prove for sure is to do it in the same truck, same obstacle, same line, first with one locked, then the other.

But for now, the poster of this thread can see what the various situations and experience's are, and decide what he wants based upon the type of wheeling he does.

We really need to work on keeping the personal attacks out of these threads. For goodness sake, just post your experiences with the issue at hand, don't try to prove who's got the biggest johnson.

 

i'd say that if you're going to lock one, the front would be a better option just because it's got a few lbs sitting over it. but then you run into the issue of ifs and cv axles...i've heard that with a front locker and ifs, you run the risk of breaking cv's like crazy. if it's still you're dd then lock the rear first and once it's not your dd then drop a front locker in as well.

 

If it is a IFS rig then I would say lock the rear. you have more articulation in the rear. There for most of your traction is in the rear since those are the tires that will be on the ground the most. Alot of times, even though I have both my rear tires on the ground and one front in the air, only one tire in the rear ended up spinning because it was the one loosing traction. Ever since I locked my rear with a detroit I have been able to walk right up the obsticle's I used to struggle on. This is just my opinion, but I would say lock the rear first. No matter what you do, you will be increasing your traction.

 

ok ok I will settle this once and for all...

everyone here, just donate $1 to me, I will go out and buy an ARB front locker, have it installed. and wheel it, in every possible situation, and I will let you all know what works best, in what situation.

now,
who is going to start the donation ?

 

The point is that with an IFS, you are MUCH more likely to lose traction on one wheel in the front, and therefore need the locker more. With the extra weight on the rear and the extra articulation in the rear, you are much more likely to have traction on both wheels and not need the locker.

I can't say I've done a controlled experiment back to back on the same day, but I HAVE run the same obstacles locked front only and rear only, and the front made a MUCH larger difference.

I will be happy to perform this experiment on Sunday, but it may be so icy that neither will show much difference.

 

Yep, I think this calls for an experiment.

You're right, Wabbit, a dynamics course would be better. Too bad I took that last year and have forgotten all of it

 

Weeeee and experiment on Sunday!

 

I have 1990 4runner, 2nd Gen. Front IFS , running 32"

I use 60% street, 40% ocassional "recreational" offroad. I have the same question.

I think that could be better have front locked, because in my experiencie, rear "copy" best the terrain and front almost always one wheel is on the air...

Im thinkin to get aussie locker for the front...

http://picasaweb.google.es/paulo.cardenas/4runnerTest

http://picasaweb.google.es/paulo.cardenas/Chacabuco4x4



I cant wait the results of the TEST. Anybody has IFS and ARB front and rear???

 

Unfortunately, I could not do the test yesterday as one of my manual hubs was only being held on by 2 of the 6 bolts and I'm afraid if I put it in 4WD, I will break the remaining two bolts.

Once it gets fixed though, I will be happy to do the test and take some video of it.

 

I ran all the numbers and put together a spreadsheet on this (hey, I had 10 minutes to burn at work before quiting time ) and determined........ There's no difference!

I assumed the vehicle remained level during the climb, so no left to right weight transfering (sum of forces on left tires = sum of forces on right tires).

I assumed an open diff will transfer power in a 1:1 ratio (so if a spinning tire is providing 50 lbs of tractive effort, the non-spinning tire is also applying 50 lbs of tractive effort). I'm not really sure if tractive effort is a term... but there's something along those lines that railroad people use to describe pulling power of locomotives.

I assumed the coefficient of friction was the same under each of the 4 tires. I assumed static = dynamic friction (I don't think this assumption affects anything though).

So in a 'perfect' scenario they are equal. The particulars of your situation (namely left to right weight transfer and coefficients of friction) will determine which one does better. Oh, and angle of the hill doesn't matter, it's all the same until you role over, then both choices are losers

 

I have Aussie Front & Rear. Put the front in first. I'd do the same again. Have manual hubs. Agree with the argument that the axle that lifts first needs the locker. Prevents drivetrain breakage, as long as you unlock hubs on dry pavement.

 

I thought some more on the drive home and need to post before I forget what I was thinking....

Assuming static friction > dynamic friction, you'll want the locker on the axle with the most weight on it. So for most trucks this will be the front.... but at a certain incline the rear will be weighted heavier, so it's a trade off between level wheeling and hill climbing. For trucks that rear heavy (I see a lot of pics of people with elephant killer rear bumpers with big spare tires and fuel cans hanging off of them), you'll want a rear locker unless you're backing up stuff.