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Old 09-14-2007, 01:54 AM   #21 (permalink)
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I have the 2001 LTD so it also have the rear lim-slip diff, do I need to be using special limslip gear oil for the rear and normal hypoid gear oil for the front?

It doesn't say in the manual?

One thing it does say in the manual is tht brands of oil should not be mixed, so does that mean I shouldn't refill with different brands without some kind of a flush or only that I shouldn't top up?
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Old 09-17-2007, 01:04 PM   #22 (permalink)
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a good idea would be installing a 1.5 way clutch-type limited slip differential such as one from Deftforce or Kaaz... the VLSD usually ends up getting worn out.

we usually refer to the stock nissan VLSD as V-open.. basically when it's worn out.. it might as well be open.
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Old 09-17-2007, 01:50 PM   #23 (permalink)
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can you have torque bind with an VLSD?
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Old 09-18-2007, 10:44 AM   #24 (permalink)
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Quote:
Originally posted by mtlsuby
can you have torque bind with an VLSD?
Do you understand the concept of Limited Slip Differential?
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Old 09-18-2007, 11:30 AM   #25 (permalink)
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Quote:
Originally posted by Zap


Do you understand the concept of Limited Slip Differential?
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Old 09-18-2007, 11:58 AM   #26 (permalink)
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On the newer soobies, they use the ABS in conjunction with a traction control to give you "lockers" on all front wheels. The computer basically applies the brake's to the wheels that are slipping. This transfers power to the wheel's that are not slipping (have traction). As long as you have one wheel with traction, you won't get stuck.

On older soobys, you can almost do the same thing if you have an automatic. You lightly apply the brakes while giving the car gas. On manuals you can apply the parking brake slightly (not allowing it to latch.)


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Old 09-18-2007, 12:58 PM   #27 (permalink)
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Torque bind will generally result from a worn or locked up center differential. Side to side tire drag can happen with full lockers, but never with a Limited Slip. There is just not enough side-to-side grip by the limited slip to prevent the tires from rotating at different speeds.

To give you an illustration, in the snow driving that I have done, I have found I will get stuck on a snowy hill as the wheel on the right side spins and digs in and the left one just stays there motionless. It is eternally frustrating to someone who own's a vehicle with lockers.
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Old 09-18-2007, 02:05 PM   #28 (permalink)
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Quote:
Originally posted by Boxxerace
Torque bind will generally result from a worn or locked up center differential. Side to side tire drag can happen with full lockers, but never with a Limited Slip. There is just not enough side-to-side grip by the limited slip to prevent the tires from rotating at different speeds.

To give you an illustration, in the snow driving that I have done, I have found I will get stuck on a snowy hill as the wheel on the right side spins and digs in and the left one just stays there motionless. It is eternally frustrating to someone who own's a vehicle with lockers.
Thats not true. Limited slip differntials are the same viscous unit thats in the center diff of a manual tranny. you can destroy them by having miss matched tires left and right.

There are basically two types of LSD (three including computer operated clutches). The mechanical units use either a clone clutch, a clutch pack, or the extreemly complicated haldex (torsen).

http://www.torsen.com/products/T-1.htm
http://auto.howstuffworks.com/differential4.htm
http://auto.howstuffworks.com/differential5.htm

The other type is the viscous unit. The Older style (cone and clutch pack) are always transfering power to both wheels equally no matter the conditions. When the car turns, one wheel spinng faster then the other will overrun the clutches and disconnect one wheel from the power. The mass and traction of the tire is transmitted to the clutch springs. This is wny positraction is great in straight line acceleration, trailer towing, etc, but can be a little dicy in snow and ice. With snow tires they are great, and unstopable with studs.

A viscous coupling is a differential waiting for slip to happen, unlike the mechanical units. When one wheel starts to spin faster then the other, the fluid heats up, expands, and "connects" both axles. Another veriosn of this has the fluid inside a piston, and when it expands it engages the clutches.

You can destroy either LSD with mismatched tires. The advantage to the VC over the mechanical is a better feel in turns (as they age the mechnaical can become grabby), and less drag so better gas mileage, and less weight (less parts cheaper to make). The disadvantage is that a wheel has to start to spin for it to operate.

Torsen is best suited for performance cars. Both wheels need to have traction in order for it to function. If either wheel looses all traction, it wont shift power. A torsen can be designed to multiply the torque sent to the wheel with more traction. Most torsen differntials have a manul differnetial lock because if it looses traction, just the one tire spins.

You can see how a mismatched tire can burn out any LSd (though I am not sure about the torsen yet).

Lockers are a completly differnet animal. They override the function of the differntial and lock both wheels together. One can argue in this mode that its really not a differntial.


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Old 09-18-2007, 02:26 PM   #29 (permalink)
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A spool eliminates the "differential", however a locker does allow the inside or outside wheel to rotate at different speeds. A detroit locker tends to lock the wheels together only while on the throttle. Goofy for the street and bad for your tires, but if you coast or stay off the gas somewhat the locker "un-locks" and allows you to turn without dragging your tire.

Edit: I'll add that my experience with the LSD is mostly with our manual tranny OBXT. It never binds and always "one wheel spins".
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Old 09-18-2007, 02:46 PM   #30 (permalink)
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http://www.offroaders.com/tech/limit...ferentials.htm

Really good explinations.


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