Question about posi traction, locker, etc.

RideontheEdge · #1 07-12-2011, 02:46 PM

Alright, so i'm curious and possibly a little stupid. Can someone please explain what the difference is between posi traction and a locker, if there is any. I've heard people tell me to get posi traction if i plan to ever do any serious offroading, if any, and now i see stuff about lockers. I know that in a normal two wheel drive like mine that only one wheel ever has power at one time (right?), so posi gives both wheels power. So i'm just confused now.

Someone enlighten me, i'd really appreciate it.

matt224 · #2 07-12-2011, 03:38 PM

Posi and LSD are essentially the same thing; though a true posi would allow no wheel slip at all, whilst a LSD would allow minimal slip before locking.

There are essentially three types of difs; open, lsd and locker. Open diffs are what is equipped on your truck, only one wheel receives power at any time. A lsd can function in two ways, clutch or cone driven. A lsd allows both wheels to spin until something overpowers the clutch/cone; on a performance car, this would occur during a sharp corner, the wheel inside the corner would stop getting power. A locker will always transfer power to both wheels no matter what (through a mechanical design, LSD difs must have a friction modifier), unless you have a detroit locker which will unlock mechanically.

RideontheEdge · #3 07-12-2011, 03:45 PM

Okay, that makes more sense now. Thanks for the info man! That's really been bugging me lately. Lol.

HazardousRanger · #4 07-12-2011, 03:48 PM

so essentially a lsd is better? unless you got the detroit?

matt224 · #5 07-12-2011, 03:54 PM

Depends on the application. A detroit locker is still mechanically controlled, which makes for a very unpleasant noise and clunky feel whenever it engages/disengages; it doesn't have very good street manners is what I am getting at. As for a LSD being better than a full locker, it depends on the application. A locker is best suited for extreme uses such as heavy offroading as the lsd clutch/cone can be overpowered in heavy offroading when you don't want it to. A locker is also generally more reliable as it is mechanically operated and is simple in design; but I do agree that a lsd is best for just about any appliaction for some extreme circumstances.

HazardousRanger · #6 07-12-2011, 03:57 PM

i want something for the rear end im 2wd and an lsd seems like the best choice since it is still my daily driver but id like a little better work when offroading

thanks

matt224 · #7 07-12-2011, 04:00 PM

I'd definately just go lsd unless its a dedicated wheeler.

or you can go all out with an ARB air locker, probably the best setup to have

HazardousRanger · #8 07-12-2011, 04:03 PM

details?

RideontheEdge · #9 07-12-2011, 04:07 PM

I feel like an ARB locker is really expensive... Haha.

matt224 · #10 07-12-2011, 04:07 PM

Essentially is an unlockable, locker.

http://www.arbusa.com/Products/Air-Lockers/10.aspx

HazardousRanger · #11 07-12-2011, 04:12 PM

def going with lsd type set up someday

RideontheEdge · #12 07-12-2011, 04:40 PM

Quote:

Originally Posted by HazardousRanger

def going with lsd type set up someday

Yeah, me too for sure. Hopefully sooner than later.

Kristoffer · #13 03-06-2012, 08:02 PM

Hello i just bought a 2003 Ford Ranger xlt 3.0L v6 I was wondering if it had posi traction

JGiddy · #14 03-06-2012, 08:08 PM

Quote:

Originally Posted by matt224

or you can go all out with an ARB air locker, probably the best setup to have

And what sucks is they discontinued it for the Ranger! There is another company (Eaton?) that makes an electronic locker just like what you find on all the new high-end 4x4 pickups and SUVs. Its pushbutton/open to fully locked, just like the ARB. Maaaaajor bucks though.

TRWXXA · #15 03-07-2012, 08:10 AM

Quote:

Originally Posted by Kristoffer

Hello i just bought a 2003 Ford Ranger xlt 3.0L v6 I was wondering if it had posi traction

There are several ways to find out...

Look at the bolts that hold on the differential cover. On one of those bolts there may be a metal tag. Look for the numbers that indicate the gear ratio. If it reads something like, "3 55", that would be an open diff with 3.55 gears. If it says, "3L55", that would be 3.55s with a limited slip differential.

You can read the axle code off the trucks door tag. Search the forum or Google it, there are plenty of door tag decoders out there.

Or...

Jack the rear of your truck up so both wheels are off the ground, put transmission in N with parking brake off, then grab one of the rear wheels and give it a spin. If the other wheel spins in the same direction, you have a limited slip differential. If it spins in the opposite direction, it's open.