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LSD, Anti spin diff???? Correct terminology

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Mopardude

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Someone set me straight on this. The old mopar "posi" like unit was called Limited Slip Differential or LSD for short. From like mid 90's on the trucks the "posi" like unit is called Anti-Spin Differential I know this for sure because most of the trucks I have ever owned have had this and I have made the dual tires marks in all of them to prove it! LOL My understanding was the LSD units on mid 90's and up trucks are open differentials. Lately I have had several guys tell me the LSD on the mid 90's and up trucks are "posi" like as well. Can someone clear up this confusion for me?
 
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I know my 97 4x4 Sport spin's up both 35's real easy . This should be interesting when the snow starts flying . lol
 
bremereric said:
Sure Grip is the phrase Mopar uses.
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Like 30 years ago not for anything late model.

If anyone is curious what I found out by doing some research on other Dodge Truck forums site is that the Anti Spin is the "posi" like unit and LSD is kinda "posi' like until the rotation force of the axles differ than it begins to slip and not be "posi" like.
 
Mopardude said:
Like 30 years ago not for anything late model.

If anyone is curious what I found out by doing some research on other Dodge Truck forums site is that the Anti Spin is the "posi" like unit and LSD is kinda "posi' like until the rotation force of the axles differ than it begins to slip and not be "posi" like.
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In my 1989 Dakota factory service manual it is still called Sure Grip.....Group 3 page 24. Crack open a newer factory service manual and see what they call it. I am curious.
 
bremereric said:
In my 1989 Dakota factory service manual it is still called Sure Grip.....Group 3 page 24. Crack open a newer factory service manual and see what they call it. I am curious.
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Not sure but you made me curious now too. Trying different google searches I really don't find a clear cut answer to this. Perhaps Sure grip is a brand name of who manufactures them? Something I do find more curious is there seems to be a lot of hits regarding sure grips in relation to Dakotas and hardly any for Rams. Maybe since the Dakota uses the 8 1/4 that has been around forever? Would it still be a sure grip if you had the 9 1/4 on a dakota?
 
My 98 SS/T has 3.55 gears with a Anti-Spin Differential but I believe it was called a TracLoc. The options list calls it Anti-Spin differential and I got the list from a dealer.
 
Mopardude said:
If anyone is curious what I found out by doing some research on other Dodge Truck forums site is that the Anti Spin is the "posi" like unit and LSD is kinda "posi' like until the rotation force of the axles differ than it begins to slip and not be "posi" like.
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Limited slip, posi, anti-spin, and trac-lok (which is what my 02 Dakota's 9-1/4 is termed in the FSM), just to name a few, are all basically the same thing. They are not necessarily built of the same design but they all slip when you turn a corner otherwise the inside wheel would scrub because it travels a much shorter distance than the outside wheel. Therefore there are 3 basic types of differentials. An open differential, a limited slip, and a spool.

"Posi" is an original Chevy term and easy to remember so that's what a lot of guys call them even if there not a chevy rearend.

Also note that it's possible to leave 2 black marks with an open differential. Torque in the forward motion naturally twists the rear axle upward on the right side so that's why most of the time the right wheel spins. When it lifts up it's the same effect as weight taken off causing loss of traction to the right side and transferred to the left side causing it to bite. My old 93 Dakota I used to have had an open differential and would spin both wheels most of the time because I had the rear suspension dialed in tight.
 
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