my recently acquired 68 rs/ss has an open diff.(12 bolt)...gonna put a locker(posi) or limited slip in it when i change gears....anybody have opinions on this?....what brand?...should i upgrade axleshafts too?

thanks,

bohuntr

 

Posi is a limited slip.

 

if u plan on driving on the highway dont use the locker. limited slip is the way to go. if your talking about the rear end i will be using a strange 12 bolt, a moser 9 in is similar. a little tougher maybe, and a 12 moser is about the same as a strange. there all good rearends. if u r talking gears only i dont know. lol. dont do gears so havnt had reason to look into them.

 

posi traction rear ends lock the two axles together under power,but also allows for differential in tire speed when turning(unlike a "spool")...limited slip lets the tire with the least traction spin slightly before the other axle "locks" together with the other axle...and is much safer on slippery surfaces...but sometimes has maintenence issues due to extra moving parts(clutches)...unlike the "locker"(posi)which is reletively bulletproof.(at least a detroit locker is anyway)

2 cents from a lifelong "rockcrawling mudslinger"

82 jeep cj7..with a lt1 from a 93 camaro

bohuntr

 

fyi like pete said limited slip is a posi. an open rear end is where the wheel with the least traction will turn. limited slip has clutch plates and the open setup has star gears and no clutch plates.

 

Fwiw when I redid mine I went with an Eaton posi, Richmond gears and upped my axles to 30 spline Mosers from the stock 28's for added insurance. Do you want the posi so you can get even wear from your tires?

 

didnt want to start i tiff here...but there are 5 kinds of possible setups on a rear end:

1. posi-traction(locking differential..axles locked together under power)
2. limited slip(axles not 100 percent tied together under power...but close..depends on quality/brand of unit)
3.open(tire with least traction spins)
4.spool(ties the two axles solidly together)
5.welded(spider gears welded together)

its not an opinion...just facts

i guess it depends on who you ask,i guess....but i think "posi" has become kindof a generic name for limited slip...even though its not even close to the same setup(other than it replaces carrier/spider gears)

i'll prolly go with a quality limited slip since i ain't gonna be racing

bohuntr

 

Are you posi about that?

 

pun intended!!!

bohuntr

 

Positraction, or posi, is the brand name for the original Chevy limited slip differential. Positraction uses clutches lo lock the axles together. However, the clutches can be overpowered and slip. GM also uses the torsen (Torque Sensing) type differential which sends power to the axle with the most traction, torsen does not use clutches. Also there are other types, like "Detroit Locker" that always lock the two axles together until one axle is forced to spin faster than the other, such as when going around corners; these do not use clutches. Fully locked differentials use a spools or welded spider gears; these make it difficult to go around corners, and should an axle break they will cause a sudden turn towards the broken axle side.
http://en.wikipedia.org/wiki/Limited_slip_differential