Can someone explain to me the what exactly it does. advantages of it etc...

I know my truck has it with the 373 rear.

pretty noob question but something I have never really learned.

 

Power goes to both rear wheels with LS. Limited slip is Fords term for positraction. Positraction is more or less a GM term.

Power to both wheels = better traction.

 

A open diff will allow the wheel with less risistance to spin. That makes for the one wheel peel traction braking and the inside tire spinning coming out of a corner on the gas. With a Ls clutch packs enguage and help limit the amount the tire with less resistance can spin before it applies power to the other tire. While it still does slip when enough force is placed on opposing wheels it is still better than nothing and helps offroad and when traction is poor. LS are preferred to lockers on vehicles that spend alot of time on the pavement as they are much smoother and more quiet then a mechanical locker.

 

Yeah, that's what I meant

 

I see....

thanks for the info

 

1 thing about it though. It seems hard to engage at times. I was told not to just gas it, but rather let off the gas and gently press the gas and then the LS should catch. I haven't tried it yet, but I had trouble with mine even engaging in the past.

 

Well - there's always Google ...

http://auto.howstuffworks.com/differential3.htm

 

Just want to let you know that "limited slip" is not a "Ford Term", but an industry wide term for the type differential used. "Positraction" is not the same as a "Limited Slip". Positraction was a permanently locked differential, while Limited Slip is an "open diff" that only locks the diff. when wheelspin is detected.

FYI, most Factory Limited Slips are not very reliable and will go out over time. Mine went out at about 75K miles on my '04 Screw 4X4. Since I bought the 100k mile warranty I elected to have it replaced with the factory unit since it was "free", but should I have to replace, I will buy a "Selectable Locker" like the E-Tec or ARB.

 

I beg to differ. Posi and LS are exactly the same thing. A locker does just that.....it locks both wheels together placing a locker in a category of it's own.
I believe Mopar call theirs Trakloc. These are simply brand names, and like I said, GM refers to theirs, or at least used to in years past, as posi.

Now, I may, just may be mistaken here, but if somebody can prove me wrong with some solid evidence, then I stand corrected. Lord knows, it wouldn't be the first time I've been wrong.

 

It should not be hard to engage at all. I have the factory Ford Trac-Lock in my Mach and when I launch both wheels hook and go. If I use the Line lock to lock the front breaks and do a 2nd gear burn out both tires start spinning right away. If I peel out I leave nice even tracks. My point is if your getting a one wheel peel before the clutches lock and start spinning the other wheel you might want to have it looked at.


Not sure about your situation but chances are unless you broke the housing itself all they did was re-build your existing diff. Thats the great part about the Ford diff. For about $45.00 and an hours of time you can re-build it to new in your driveway whenever you want.

As for reliability I can honestly say the Ford unit is pretty reliable. Alot and I mean ALOT of Mustang guys run them with great success. I ran one in my nitrous GT for almost 2 years with probably 3-400 5000rpm launches and low 12 sec e.t.'s, have had one in the Mach since it was about 2 weeks old and it has lord only knows how many 6K launches on it and it is running perfect. On the GT I pulled it after two years of hard use and it looked pretty much like new with minimal wear, same thing the last time I inspected the diff on the Mach.

 

The LS in my 95 Mustang is and has been rock solid, and it has never been touched. The closest it's ever been to being touched was when I did a gear swap.
The "posi" in my last 2 GM trucks were about the only solid things about them

 

You are correct, GM coined the term "Posi-Traction" for their LSD back in the muscle car era of the 60's.

I don't think there is a car manufacturer around that would put a "Locked" rear end into a car that is to be sold on the open market. If you have ever driven a car with a truely locked diff you will know what I mean when I say taking a turn at any decent rate of speed would be dangerous as well as wreak havoc on the rear diff.

 

lol... yes, I have, and I've also pushed a few while trying to turn/steer them at the same time. Major PIA!

 

I love how people say that Ford LSDs are weak and unreliable. Funny, I've never had a problem with any of mine or know anyone to have a problem with theirs.

 

Instead of explaining it from a technical point of veiw let me give you an idea from a driver's seat veiw:

It means starting off from a stopped position on gravel no more spinning out (unless you step on the pedal pretty heavy). It means on rain slick roads when you take off from a stopped position and have the steering wheel turned tight no more spinning out (unless you really puch it). It means starting out from a stopped position pulling a trailer on wet dewey grass no more spinning out, usually (again unless you give it too much throttle too quickly).

To me it's a very worth while option for any pick-up. If I remember right it adds around $300-350 to the total price of a truck. Kind of like a poor man's four wheel drive. It won't get you through, over, up, Etc. obstacles like a 4x4 but it's much better than a standard rearend.