When do you NEED posi?

[Rapid]

I have a mild 289, T5, and don't race. I am going to a 3:25 axle from the 2:79 I have to take advantage of the overdrive. I am trying to talk myself out of spending the extra money for a posi but don't know that I would be makIng the right decision. I may do some autocrossing again but mostly dirve daily and travel in the car.

Any thoughts?

 

[D.Hearne]

You need it whenever the single tire traction is overcome by the engine's torque. If you don't drag race it, drive in snow or off road, then don't spend the money. If you haven't noticed a need for it by now, you don't need it. If you were to sell the car later, it would be a plus in value to a prospective buyer though.

 

[fasttback]

IMO - get it. Improves traction and handling. All my Mustangs started out as conventional rearends are now trac loc.

I was almost in an accident with a conventional rearend because it would break the passenger tire loose in the rain on right turns so easy. This was with a mild 289 and being easy with the gas pedal.

 

[86bluecobra]

I think everyone needs it.

 

[BlwnGazkit]

For DD it benefits you in the rain and snow or any similar conditions.

 

[wicked93gs]

I dont think you need a full locker type rear end...but a Posi trac(limited slip) rear is definately a plus...the question is simply whether you'll kick yourself later for not getting something that will allow your car to get better traction...especially if you decide to start racing down the road, I'd get it if its not much more

 

[ron67fb]

Owning the car since 1989 I've only wished I had it a few times, mostly in the rain making a right turn at a busy street. The RR tire would just spin and it was hard merging with traffic even when trying to feather the gas. Now while driving it less than 500 miles a year and it only rains maybe 20 days a year here I really don't care, but I'd like to get it someday just for peace of mind. If you're already taking the rear end apart and have the extra cash I'd say go for it.

 

[Rapid]

Where did you get the Trac Loc?

 

[D.Hearne]

Seems to me none of you have ever driven a trac-loc car with lots of torque. My 67 big block Stang was a terror to drive on slick roads. Or rounding a corner and nailing the gas too hard. It more than a couple of times wanted to swap ends in traffic. My 06 has once puckered the ass when mistakenly downshifting from 4th to 2nd on a slick off ramp. All due to trac-loc. My Ranger's done the same a few times to, with the kid driving it. Once you have it happen a few times, you learn real quick to control your right foot. If none of you have experienced this, you have yet to drive it to the limits. Just bewarned, trac-loc isn't a cure for the uninformed, it's got it's downfalls too.

 

[fasttback]

Seems to me none of you have ever driven a trac-loc car with lots of torque. My 67 big block Stang was a terror to drive on slick roads. Or rounding a corner and nailing the gas too hard. It more than a couple of times wanted to swap ends in traffic. My 06 has once puckered the ass when mistakenly downshifting from 4th to 2nd on a slick off ramp. All due to trac-loc. My Ranger's done the same a few times to, with the kid driving it. Once you have it happen a few times, you learn real quick to control your right foot. If none of you have experienced this, you have yet to drive it to the limits. Just bewarned, trac-loc isn't a cure for the uninformed, it's got it's downfalls too.

I think we all have at one time or another. That's the fun part of having two wheels with power.

Overall the Trac Loc provides better traction - IMO, but if you break it loose and don't let up...be prepared for one hell of ride. It's all about knowing what you car is capable of and how to control it.

 

[sburkey1967]

refreshing

to see that nobody tore him up for referencing "posi" traction. I posted the exact same question when I first started researching what to get and got tore up by a couple gear heads who were completely offended that I called it "posi" traction instead of limited slip or traction lock or whatever it is called. lol The point is, you knew what I meant when I asked it. lol

This wasn't in this forum either!

 

[D.Hearne]

Trac-loc, limited slip, posi-trac-------it's all the same thing to me, all are clutch type differentials and do the same job. Sounds like you got ahold of some nit- pickin nit-wits

 

[zookeeper]

Seems to me none of you have ever driven a trac-loc car with lots of torque. My 67 big block Stang was a terror to drive on slick roads. Or rounding a corner and nailing the gas too hard. It more than a couple of times wanted to swap ends in traffic. My 06 has once puckered the ass when mistakenly downshifting from 4th to 2nd on a slick off ramp. All due to trac-loc. My Ranger's done the same a few times to, with the kid driving it. Once you have it happen a few times, you learn real quick to control your right foot. If none of you have experienced this, you have yet to drive it to the limits. Just bewarned, trac-loc isn't a cure for the uninformed, it's got it's downfalls too.

You got that right. For those that think a posi is a big plus in the rain, I'd bet money you've never driven anywhere near where I live. I'll take slipping a rear tire under acceleration as opposed to swapping ends anyday of the week and twice on Sunday. A posi is great at the drags and fun when you're getting after it on the street, but lots of horsepower and a heavy foot in the turns will educate a rookie in hurry. Now watch someone from Phoenix, Arizona post how great his posi works on wet streets...

 

[bnickel]

trac lok does help in rain driving by getting traction to both wheels so the one wheel with power doesn't just sit there and spin, but can get you into trouble at the same time if you aren't used to it. my opinion, get it since you're there anyway

 

[D.Hearne]

You got that right. For those that think a posi is a big plus in the rain, I'd bet money you've never driven anywhere near where I live. I'll take slipping a rear tire under acceleration as opposed to swapping ends anyday of the week and twice on Sunday. A posi is great at the drags and fun when you're getting after it on the street, but lots of horsepower and a heavy foot in the turns will educate a rookie in hurry. Now watch someone from Phoenix, Arizona post how great his posi works on wet streets...

Back in the mid 80's I was up in Indian country in north Arizona, in an 85 Pete pulling a flatbed with 5,000 lbs of cargo (like nothing at all) and encountered light rain shower, that asphalt was exactly like driving on ice. Must not have rained there in a year or more. I drive in rain weekly down here, and I'll take that anytime over wet roads in Arizona.

 

[ultrastang]

Trac-loc, limited slip, posi-trac-------it's all the same thing to me, all are clutch type differentials and do the same job. Sounds like you got ahold of some nit- pickin nit-wits

Here comes the nit-pickin nit-wit....

Original question: "When do you NEED posi?"

Answer: When you have a GM product.

In the same train or thought, a Mercedes, Lambo, Volks Wagon, Yogo, AMC Pacer and Mustang all perform the same basic function, but I don't call my Mustang by any of the other names listed. I call it by it's proper name.

There were three different terms used by Ford to describe differentials produced by them, that directed power to both rear wheels:

1st version was known as "Equalok". This came out in '57 and was used through sometime into the early '60s.

2nd version was termed as the "Limited-Slip." It was available from the early '60s through 1968. --I don't know this to be a fact, but think the Equalok and Limited Slip differentials are actually the same thing, --just renamed.

3rd version came out in 1969. In the cars it was available from '69-'80. In the trucks, it was available from '69-'85.

--There was also a 4th version used by Ford, but not produced by them. It is known as a Detroit Locker.

Actually, you can call the differential whatever you want, but now you know better than to use the improper term.

http://ultrastang.com/Rearinfo.asp?Page_ID=2

 

[Opentracker]

You need it anytime the car is in motion. While the car is at rest, a one leg'er is OK but other than sitting at the car show, well, they should both work. A line lock is also a must with a dual traction unit.

 

[runawayabc123]

I was always under the impression limited slip was bad in the snow since one wheel slips a little and the other keeps going, you spin out whereas a convention diff would just let the one wheel spin and the other would slow down and just cause a little fish tall.

Sure, if you got stuck, both wheels moving is good to get you out, but if you are good enough to not get stuck, when/how does the limited slip help in the snow?

 

[Rapid]

MAER's site calls it a Trutrac posi. Is there a better place to buy a complete 3rd member or do these guys do it well? There is a place on Ebay taht has good ratings offering a similar service.

 

[D.Hearne]

Currie and one other, that slips my mind sell complete 3rd members too, in addition to complete rears.