I’m planning to upgrade my rear differential and would like to install a posi system. This is a weekend cruiser for me. I’m not sure whether to go with a limited slip posi, or a locker. Any thoughts or suggestions?
Myself… I’d Rather have the locker! Absolute posi! More “hardcore” ! Might take a little getting use to it. Cornering under acceleration will lose traction more easily, due to the way a locker works! Especially wet conditions, but you get use to it! Sometimes they “clunk”, which can sound broken, but it’s normal, and doesn’t happen often. Whenyou put down the power… It WILL be positive traction!! No slip whatsoever! Had one for many years! If you use slicks ever, you won’t be sorry! Also, when you losen or tighten lugnuts, you must lift both wheels off the ground to prevent damage, according to the owners manual. Limited slips work good, but cluches wear out, and they slip more. Also they chatter around turns occasionally, and sometimes always! They have additives for that, but it is just super lube to let them slip more easily. Both have there advantages and disadvantages… Like I said earlier…I go locker! Good luck!
How is the locker around town, parking lot, etc.? Do you get much tire chatter?
I’ve always had (factory) Traction-Lok differentials in my car and have been happy with them for the most part. They have to be rebuilt every once in a while, but it’s typically a pretty easy process. They start to do a “one wheel peel” when the clutches are worn out. I think I’ve only had one chatter maybe twice (in my '08). You can add more friction modifier, but it ends up just making it not as effective. There are quite a few different types of limited slip differentials out there any more and most work fairly well. One other type you might look at is a Torsen. They use gears and mechanical advantage to get traction to both tires. They don’t chatter or clunk like the other types do. They’re also not very cheap. My '68 currently has a Traction-Lok in it, but will probably eventually be a Detroit Locker or something similar that puts equal power to both wheels. I don’t really care that much about the clunk and am more concerned about straight line performance.
Edit - removed DL references.
Had a locker in my’79 Camaro and while it worked great for straight line drag races, it sucked for everything else. So ask yourself,“Do I feel dealing with a lot of ratcheting, noise, and having to be prepared for ABRUPT direction changes with the slightest throttle input?” If you answered yes to those questions, then go with a locker. Yeah you will get used to a locker, but there are SO many better things to go with on the street.
Go with a decent torque biasing differential that offers GRADUAL engagement.
You guys are referencing older technology. Install a Eaton Tru Trac unit. No clutches to wear out and a lot nicer on the street then a Detroit Locker which Eaton also makes. I run a Tru trac in my road course prepare Cougar. Only run the Detroit Locker if you want straight line full lock for drag racing or for off road vehicles that need both wheels lock going over uneven terrain.
What Brian said. I use one in Isabel and it works flawlessly. No friction modifier required (as with clutch limited slips) either.
Now, where’s Royce to expound upon how Detroit Lockers are no problem on the street? 
I had Traction Lock posis in my cars years ago. They don’t hold on a hard launch with a good engine. They wear out in a few thousand miles, then you need to tear them apart and replace the clutches.
I switched to Detroit Lockers 30 years ago. The notion that they are noisy is false and baseless. They last forever. No special oil needed. Love them.
No, never. I have put 30,000 miles on my green GT-E since it got the Detroit locker.
You’ve never rode in a car with a Detroit Locker.
Just buy yourself a Eaton Tru Trac, and forget about it!
TruTrac is what I’m putting in mine. Everything I have driven with one in it has driven well, the engagement is linear, and it just plain works without the noise, sudden direction changes, etc. Great unit.
It’s been 20 years. I apologize for the incorrect description. The ratcheting is constant, not just once (amongst other things). I went back and edited the bad info out.
Locker around town is just fine!!
Yes, lot of parking lot and tight turn chatter. My Eliminator has Detroit Locker. It’s good for straight line cars.
I run a Gold Trac in my Shelby, best differential I have had. Works great at the track and on the street.
And our 68 has a 31 spline traction lok. Works great on the street.
My opinion is if you are going to buy a new diff to install go with true trac, but if you find a good deal on traction lok at swap meet/classifieds it would be fine on the street. I have all three types, and I agree with all comments posted before with the true trac and traction loks, but my locker is not the most civil on the street.
So there’s what Royce and Johnny say about lockers and then there’s everyone else…
Yeah. Just don’t say you weren’t warned if yo go with one.
Another True Track here. Put one in Pole Cat last winter. I have never heard or felt a peep out of it even with my hearing aids in.
The Detroit Lockers that were made in the 1960’s - early 1970’s are not like the ones made in the late 1970’s - until today. If you have an old original one those rare birds are where the stories come from. Those units make a click - click - click when turning sharp at sub walking speeds on concrete if they are in good shape. It is a glorious noise that warms the soul.
The Detroit Lockers of the past 40 or so years are dead silent, don’t make any noise at all.
Royce, my locker is from early 90s. It’s not loud (click, click, click) but tires chatter in parking lots and tight turns. When comparing locker to gold trac for drivability, gold trac blows it away. Just in the fact that so much more forgiving on trail throttle. I’m just giving my honest opinion on what my personal experiences are. I drive my cars around town and at the track. Like I said before before, I have all three types in two cobra jets and a supercharged stroked small block. For a street car I say a true trac is the best choice. Everyone has their own preferences, and I respect that, hopefully my information is helpful to the discussion.
Dave