So, just to clear things up, a person can tell the difference between a limited-slip/Posi-traction rear-end and a locked rear-end that is off the ground by spinning the wheels? If both wheels spin backward together it's locked, correct...? And a posi-rear-end will only spin forward together??? I've had Datsuns with locked rears, and I know plenty of 'wheelers' rigs that are locked, but how shitty does the drive become in a hot rod/custom? Any horror stories....? I understand the math (the outside tire squeals because it needs to be spinning faster than the inside tire and "locking it" spins them at the same rate); I just don't get the whole "you don't want a daily-driver with a locked rear" mentality... Fucking Lincoln-locker.... guess I need to practice drifting.....
posi /limited slip are the same thing ,ford called it one thing and gm called it something else. even what most call a locker arent ,ie gov-lock.really just a clutch type posi.if it has a friction clutch beside a spidergear ,its a posi/limited slip.truetrac also a posi/limited slip.has gears that work together to preload the side gears .but its NOT a locker.detroit locker is a mechanical locker.lockers the (side gears ) together..air locker ,uses air presure to lock the side gears together but it becomes a spool.will not ratchet like a detroit locker....i have a detroit in my 53 ford car..run it daily ....alot of import axles are pretty tight and feel like a posi but arent....
big diff between welded and locker.when coasting the locker will ratchet letting the inside tire turn slower then the outside.with a spool/weld the tires turn the same speed all the time no matter what.wears tires, rough on drive line parts and no fun on wet roads
The Detroit Locker in my 55 is pretty easy to tell from a spool/posi/open rear...it ratchets. Jack up one wheel, take it out of park, you can turn the wheel and feel the ratcheting. A LSD with moderate springs or worn clutches will let you turn one wheel also. A guv lock may grab if you spin one wheel fast enough in neutral. A tight LSD acts like a spool when turning wheels by hand. The limited slip Dana 40 that was in my old truck has no springs, just clutches, and spins freely by hand, but it's a posi. I guess you can generalize, but you might come up with the wrong answer in some situations if you do.
I have a rear end being built right now, and Im using a True Track brand posi, the builder told me on jackstands it will spin like a non-posi. I guess its what nascar is running.
Yeah, the true track has worm gears in it...easy to turn one wheel by hand, but hard for it to spin only one wheel by turning the driveshaft
I agree with squirrel. 440, your experience may have been in LWB cars, so it would be harder to tell, but in a SWB car in a tight turn it's pretty easy to feel it and if they bind a little, you can hear the tire chirp a little before it rachets. As for a spool, I'm not sure how you wouldn't feel it, even in a LWB car. Also, as 440 suggests, do not run a welded (or even a spooled) axle in a street car. Makes no sense at all. I don't see a problem in running a detroit in street car and will be in my '33. It takes some getting used to, but if you know what to expect, it's no problem. Having said that, 90% of the people out there just need LSD (not the drug! ) greaseball, raise the rear wheels off the ground. Place the transmission in low gear and see if you can turn the drive axle wheel by hand. If the drive axle is a LSD, it will be hard to turn the wheel-or maybe not turn at all. If it's an open diff, the wheel will turn easily, and the opposing wheel will rotate in the opposite direction. Next, put the transmission in neutral and turn the rear wheel. If the axle is a LSD the opposite wheel will rotate in the same direction. If the diff is an open type, the opposite wheel will rotate in the opposite direction-or not at all.
Yup...... About the only thing you can be sure of is that if the opposite wheel easily turns backwards, it is a fully open diff. If in the same direction it is "something else". It is the "something else" that is the problem. It could be just about any type of locked, locking or limited slip type of diff. The only way you are going to know for sure is to pull the diff and see what is actually in there. Some genius that says it has an LSD may be quite right, but it could also be be a spool, viscous LSD, clutch pack LSD (posi) or something really wild like a Detroit Locker, or a Torsen. They all have advantages and disadvantages depending on the vehicle and what it is going to be used for. There is no "best" type of diff. If one type was vastly superior, everyone would be using it, and all the other types would quickly become obsolete. But you get to choose. And what is best for you depends on what you want your vehicle to do, and on what kind of surface.
Stay away from Spools and locked rears .They suck I had a 410 in my elcamino It would hop on turns Going straight was fine. I didn't drive car much do to it was not very enjoyable .Traded a guy straight up .This rear was brand new with a few miles Traded for a used 3.31 posi Best decision I ever made
What type of rearend is it? what's it in? you're not giving us much to go on....and one wild guess is as good as another
Should be pretty easy to tell an open (wheels turn opposite directions), from a Detroit Locker (ratchets and clicks), from a locked/clutch type limited slip (wheels turn same direction) You're gonna have to pull the cover or drop out section to tell a rearend with welded spiders/spool/minispool from a good clutch type limited slip. I don't have any idea about the worm gear and dual pinion type rearends. Larry T
A limited slip dif will only spin on wheel at a time, this is made by ford. A positive dif will spin both wheels at the same time, this is made by GM. As we all know GM is located in Detroit, thus it became known as the Detroit locker.
Both back wheels propel the car with the standard peg leg rear end, it's just when one wheel brakes loose most of the power it transmitted to that wheel.. NASCAR used peg legs in the 50s and 60s...... Checkout the video, notice the Miller 62 Pontiac throwing sand... http://www.youtube.com/watch?v=Ly2vuzs1-As
Lots of info already so I won't go into it. I have run lockers on the street since i was a kid, not spools but lockers. A spool is a locked rear for sure but most folks don't call them a locker. I have run spools also but I don't care for them the only way to actually corner with a spool is to do it dirt track style. I do like a detriot locker, it isn't like driving an open rear but it isn't bad to drive. Some of them are a little rough when you corner but it only takes a little getting used to, once you realize that it may be a little jerky you adjust and you are fine. I prefer a locker to a posi, but I think it is just a personal preference. they do not drive like an old caddy with an open rear it is a performance option. Performance cars are not designed for comfort and you have to make some concessions for going fast.
Yes. "Positraction" is just a brand name that has come to be used for every type of limited slip differential, much like every facial tissue is a "Kleenex". Not even all of the G.M. makes used the term; if you ordered it for your new Pontiac, it was "Safe-T-Track".
Detroit Lockers are now produced under Eaton's name. We Just put one in an early Falcon....fantastic. Lockers drive the inside tire until the inside speed matches the outer. This could drive the vehicle toward the outside @ partial power. Haven't noticed anything on this particular installation, they are even quieter (fuel pump is much louder) than old ones w/ a variety of spring tensions available. Eaton also makes Trutrac and Posi LSD under those names http://www.eaton.com/Eaton/Products...AutomotiveAftermarket/Differentials/index.htm
another thing about running detroit lockers ,,, with a automatic trans you dont notice the locking and unlocking as much,, every now and then i hear mine or it might " clunk" ....
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