whats a spool???  

It is a unit that replaces the open differential in a vehicle it permanantly and completely locks both axles together. I drove one in my Cherokee Dana 44 on the street and the dirt... AWESOME with no drawbacks handling-wise. Nice "chirping" on the street!  

It is term used for a machine piece of solid metal the replacs carrier in axle and has no direnetail action at all. Axles shafts are locked together all the time period. Not a good thing for street or off road.  

"AWESOME with no drawbacks handling-wise"

Nothing could be further from the truth about spools...

whats the difference between a mini spool and full spool?  

Design and construction. I have seen some spider gear replacements called minnie spools as well as some small light weight full spools. I strongly advise against any of them given that a detroit locker will give you the same performance in the rough and still have the abilty to free wheel the outer tire in a turn under light power or when coasting.

i am looking to buy a spool for my rear nine inch its not a good idea what can go wrong. it is my daily driver and i do some serious mudding and need traction.  

no way would i have a spool in my daily driver! that's just ridiculous! nice chirping sound??? does this guy know what that chirp is doing?
Dude, look into an E-locker or some other kind of selectable locking unit. You do not want to run a spool on the street! it would be a disaster! For someone to say there are no drawbacks, handling wise, is complete nonsense.  

thanks can you send me a link for the best E locker for 40 inch super swamps. i was looking at this trac lok posi what do you think about that and do they perform.  

You do 'serious mudding' in  your DD? Well there's your problem right there.

I wouldn't put a spool in a street driven vehicle, at least not daily driven, but that's just me. For that matter I don't even like my Detroit on the street.  

well i want a locker what should i use  

For your rig, probably a Detroit.

I don't like them on the street but it will be better than a spool.

The only reason I wouldn't suggest an electric or air locker is because if the line/wire gets ripped off by the mud you're driving through then you'll lose your locker and be SOL. And I wouldn't want to be swimming in the mud to try and fix it.  

thanks dude ill probably go with the detriot ill shop around for the best price if you know where i can get the detriot for free left me know  

i ment cheap sorry  

If you take the time to route and secure the wire properly it will not get ripped on in mud. Actually you will have a better chance on ripping off brake line flex hose than a properly sized and routes electrical control wire for a selectable locker.