Please describe the behavior of a locking differential

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I put a new center chunk in the 8" of my '65, that I bought used. It was represented as (of course) "posi". I did not ask the seller what kind of "posi." The seller said he took it out because it was too noisy. I figured, whatever.

The reason I'm posting is to get the experiences of guys with locking diffs, aka the Detroit Locker. Here's what I'm experiencing: in reverse at low speeds there is always a clunking sound. In first, when turning the wheel at low speeds, there is sometimes a clunking sound.

I changed the lube from Valvoline + Sta-Lube friction modifier to Royal Purple this weekend, and the sounds went away for about 50 miles, then came back. Royal Purple has the friction modifier already. But I added some friction modifer and the sounds went away again. But now I get a little squeal from the inside tire on low speed turns.

So that's the question: are these clunking sounds characteristic of a locker?
 
A locker yes. But not limited slip. If it has two tires spinning, most call it a posi, when you can get more detailed in how it does it. Sounds like maybe a limited unit that is unhappy. A locker won't quite with more additve, or any at all.
 
I been wondering what mine is.

Yesterday the brake locked up on the passenger side rear tire, and the other side started spinning, does this mean I have a limited slip?

I haven`t got to drive it yet, its on jackstands right now.
 
Depends on why it was spinning. If the wheels were already turning but loosing momentum, then that would be normal. If you were spinning the tires by putting your foot on the gas(and 1 wheel wasn't spinning) then you either have a worn out limited slip, an open rear axle, or broken locker.
 
I put a new center chunk in the 8" of my '65, that I bought used. It was represented as (of course) "posi". I did not ask the seller what kind of "posi." The seller said he took it out because it was too noisy. I figured, whatever.

The reason I'm posting is to get the experiences of guys with locking diffs, aka the Detroit Locker. Here's what I'm experiencing: in reverse at low speeds there is always a clunking sound. In first, when turning the wheel at low speeds, there is sometimes a clunking sound.

I changed the lube from Valvoline + Sta-Lube friction modifier to Royal Purple this weekend, and the sounds went away for about 50 miles, then came back. Royal Purple has the friction modifier already. But I added some friction modifer and the sounds went away again. But now I get a little squeal from the inside tire on low speed turns.

So that's the question: are these clunking sounds characteristic of a locker?
If you let a limited slip (clutch-type) rear axle sit for a long period of time, the clutches won't slip like they should and you'll get a "clunky" noise and feel from the rear during tight corners, like u-turns. While ratcheting lockers are a bit noisy, thye aren't that bad, in fact lots of different brands of four wheel drive pickups came with them as a fcatory option for years. I may be wrong, but I've never heard of a ratchet-style (Detroit locker) differential for an 8-inch housing.
 
Yesterday the brake locked up on the passenger side rear tire, and the other side started spinning, does this mean I have a limited slip?

I haven`t got to drive it yet, its on jackstands right now.
You have described an open rear. It transfers power from the wheel that grips to the wheel that slips. ;) Now that you have the wheel loosened again, try to turn one wheel. If the other side turns the opposite direction, you have an open or a worn out limited slip. If it turns the same direction, you have a functioning limited slip.

Daniel
 
Cool that tells me something now.

The wheels turn in the opposite directions. I`m sure its wore out, every thing else was wore out under there, this is only thing I haven`t replaced yet.
 
Wheels go opposite directions on open diffs. Possibly worn out limited slips (posi).

A locker will click on turns and such.
They use a ratchet like mechanism.
A 'posi', traction lock, limited slip, whatever you like to call it, makes no noise when functioning properly. It will generally spin one tire, then the other, but can do both at once.
I have never seen an open swap sides like a limited slip.:shrug:

I have broken a locker once as well.
They send 100% power to both wheels at all times.
If you break a locker, it will send 100% of power to the one side that isn't broken, and you will have uncontrollable wheel spin with the slightest throttle!
I broke mine on a diesel van that couldn't spin wheels on greased asphalt... :D
When it got 100% torque to one tire, I couldn't ease away from a red light without the tire on the functioning side trying to burn down!
 
If you let a limited slip (clutch-type) rear axle sit for a long period of time, the clutches won't slip like they should and you'll get a "clunky" noise and feel from the rear during tight corners, like u-turns. While ratcheting lockers are a bit noisy, thye aren't that bad, in fact lots of different brands of four wheel drive pickups came with them as a fcatory option for years. I may be wrong, but I've never heard of a ratchet-style (Detroit locker) differential for an 8-inch housing.


Here you go, Detriot E-Z Locker. This one fits both the 8" and the 9"

http://store.summitracing.com/partd...4294908331+4294839047+400949+115&autoview=sku
 
I have a 65 and personally installed a Detroit Locker in it's 8" housing. If I had to describe any sounds from the rear I would have to describe them as a sharp mechanical clanking sounds. Sometimes a sharp clank that sounds like the ratchets don't fully engage while releasing the clutch. When taking sharp right and left hand turns the inside rear tires will squeal (especially on hot glassy smooth tar) until I straighten the wheel out at slow speeds. Friction modifier and additives are redundent as there are no clutches in a Locker. I run straight 90W Hypoid gear lube.
 
Thanks for all the replies. It looks like I just have a messed up lsd, not a locker. I've got too many other things going on now to deal with it, but I think I'll switch to a Torsen (True Trac) one-a-these days.
 
There's also the possibility that you bought a rear with the "50 cent locker" which consists of taking an open rear end and shimming the spider gears to force both wheels to turn at the same time.

Problem is that this puts a lot of unnatural stress on the rear and things break or at least start to give.