Understand drive power on AWD with Limited Slip

[98EBV8]

Hi,
I have a V8 AWD (All Wheel Drive, not Control-Trac) Explorer with the 3.73 Limited Slip in the rear.

In normal conditions, what wheels get powered?

I know that when I step on the pedal on the slick snow parking lot, the vehicle want to go sideways before it stablizes it? Why does it do that? Doesn't the LS engage instantly?

On ice, I felt all four wheels spinning from stop on a icy parking lot. Is that true or both wheels in the back spins and the one front wheel spins when that happens?

Thanks,
Shane

 

[leenjen]

i'm not a mechanic but i think on the AWD system, all wheels are receiving some power. under normal driving conditions the rear wheels receive the most, but the front is still engaged (maybe 30% to the front, not sure but i heard it mentioned before). that's why the V-8 AWD systems get bad gas mileage.

 

[Haxaw]

The power of the AWD drive system is 65% rear and 35% front untill the tires slip and it tranfers 50/50. In a limited slip rear end the tires should mainly both spin in the rear, the difference is that a posi rear end will spin both all the time and an open rear end will only spin one rear tire, the limited slip is in between it helps both spin at the same time. The AWD drive system, however, will put the power to the wheels that need it, i think in the front end only though. If your left front spins then it will transfer power to the right front that is gripping more. If you have the Ex up on jack stands and spin one rear tire, in a posi they will both spin the same direction, in and open or limited slip they will spin in opposite directions. The reason everyone on this site wants a posi (dana) locker is because if you are on three wheels on a rock or something the wheel that is up in the air would spin like crazy without one and traction would be lost.
Hope I could help a little.

 

['96explorereddiebauer]

Haxaw, I have a question...My '96 Eddie Bauer comes with a 4.10 limited-slip diff. If I read your description of the operation of the posi rearend correctly, then both my rear wheels will spin at the same time nomatterwhat?? Even in turns?? I'm asking b/c sometimes when I make right turns at an intersection, I gun it and all I hear is tires chirping from my right-rear, my truck still goes but the tire chirrping is apparent. So I'm wondering if that normal.

 

[NedFlanders]

Originally posted by '96explorereddiebauer
Haxaw, I have a question...My '96 Eddie Bauer comes with a 4.10 limited-slip diff. If I read your description of the operation of the posi rearend correctly, then both my rear wheels will spin at the same time nomatterwhat?? Even in turns?? I'm asking b/c sometimes when I make right turns at an intersection, I gun it and all I hear is tires chirping from my right-rear, my truck still goes but the tire chirrping is apparent. So I'm wondering if that normal.

Your limited slip will only transfer some of the force from the tire that slips. Under normal driving you won't actually notice it at all. If you gun it in a turn you'll be more likely to lose traction on both rearwheels, because the LS will try to "drag" the non'spinning wheel along. Especially if it's slippery in any way. Same thing if you floor it when slippery, it will try to drag both rearwheels along. But it's not a fully locked diff. You'll not be able to have one wheel in the air, and have the other one drive you along. Then you need the full lock..

 

[Haxaw]

Neighbor Ned here is right

Limited splip really helps the best on ice or snow. Even in the rain you maybe able to spin both tires. You have a very high gear ratio so spinning the tires should be no problem. If you floor it staight ahead then both tires should spin the same but when there is a weight shift ie the turn, the tire that is on the same side as the direction you are turning will spin more because all the weight shifts to the other side. It's actually a good thing because is you spun both rears the ass end would kick out and maybe fishtail into another lane. That whole "an object in motion tends to in motion" even applies to the rear end of Explorers, that Newton was a smart guy huh.
By the way Ned, who in there right mind would take a VW Bus in that much snow, my buddy had a Vanagon and that thing lost traction all over the road with just a dusting of the white stuff.

 

[NedFlanders]

Re: Neighbor Ned here is right

Originally posted by Haxaw
By the way Ned, who in there right mind would take a VW Bus in that much snow, my buddy had a Vanagon and that thing lost traction all over the road with just a dusting of the white stuff.

He actually made it trough places I didn't. Like the place the one picture of my truck in the snow is taken. Doesn't look to steep, but it kinda tricky to get up. I didn't make it(but then I didn't want to just floor it and hope for the best eighter..) but he got up there. It's a fulltime 4wd with VW syncro-system, and he actually has a locker in his rear.. Not built for eighter offroad or fourwheelsskids on pavement I guess, 'cause his trans. broke in two different places within this last spring.

Originally posted by Haxaw
....turn, the tire that is on the same side as the direction you are turning will spin more because all the ....

Actually, it would be the other way around.. the tire on the other side of the truck would turn faster 'cause it would follow a longer path.. Dead Link Removed If you mean which tire is more likely to start spinning, you're correct if we're talking a totally open diff..
If you gun a LS-diff it in the turn and it's slippery, the LS will actually make the chanses of loosing traction on both wheels, since it tries to transfer power to the non-spinning wheel, and then you could end up in this fishtailingthing..
I have no problems what so ever to lose traction on both rearwheels on my explorer(with a 3:73 LS in the rear) as long as it's just a little bit slippery in some way..

Guess what I try to say is that the LS is helping you going where you want, but you can't drive it like an open diff when it comes to turns. It won't be as bad as a full locker, but it will definately...hmmm...help you if you wanna make donuts in the snow..Dead Link Removed