No it doesn't! My first trip to the track w/ a spool installed, it rained on the way home...I drove the car there. I was worried b/c of everything I'd read on the internet about spools, but it didn't act any different at all. That was on normal radial tires.
The tires have everything to do w/ how the car acts in the rain, not the spool. Driving on ET Streets in wet weather isn't a good idea. On normal tires it's no problem.
If you spin out in a curve w/ a spool, your right foot was the problem.

This is a very informative thread, should be archived imo. Any way, one aspect I've seen neglected here is cost, a spool being in the $150 range vs a Detroit locker in the $725 range for a Dana 60. I've been weighing the pros and cons of upgrading my 8.75 vs biting the bullet and going the S60 route. The S60 seems to make sense to me, spend the money once, then never worry about it again. I'm gonna go spool as well, cost effective and extremely reliable. Just my 2 cents.

I agree with 8sec70cuda.
got caught in heavy rain sunday morning, spool and nito drag radials had no problem at all.

Well us on the keyboards can never be 100 certain what is the "problem" mentioned above, but it is a simple proven fact, there has to be rear tire slippage with a spool in a turn ( unless a tire lifts off the surface when turning), period. Now if on one car, with its unique suspension, its unique tires, its unique tire pressures, its unique weight bias, its unique shocks/settings, and a host of other variables too long to list, when a driver does not experience a potential spin out, I find it hard to state the spools natural turning tire slippage can always then be disregarded.

A spool is at least predictable, it will do the same thing all the time. A locker is very quirky, you might have an open diff going around the on ramp in the rain but when you apply power you get a spool when it locks, or sometimes the decel force is enough to lock it that way and that can be sketchy. My Jeep has lockers and they do weird things, you can lock and unlock it in a long turn and feel it push on the front end and drag the tire, but if its wet you have to be careful because that transition from unlocked to locked will make it step out. Same goes for a limited slip, on a slick road they can act like a spool if they are tight, they can still cause the tire to drag on the inside.

A real good & tight suregrip or locker will still be slipping that inside tire on slick/wet pavement. Never hear anyone complaining about that.
Just about every time someone starts stating these reasons a spool is dangerous, they have zero personal experience w/ them. Hear this crap a lot and when you ask how they know this...so and so told me or they read it on the internet. It's amazing how so many of us who have actually done these things we're commenting about are still here today.
If you can't drive one of these cars around a corner on wet pavement w/o crashing and blaming it on the differential, then you need to sell it and get a prius.

So some want to include the quirkiness of a locker (which I 100% agree with) and the tightness of a suregrip ( which is a rather large variable) with the discussed downsides of a spool cornering in the wet, but nobody mentions the OP's option of a Truetrac or helical gear diff, which does not have these major downsides.

I drove mine to work today.

Hopefully I make it home in one piece....

Better say a prayer before you head home, lol. Those spools are super dangerous don't ya know?

my son drove my dart to work this morning. no issues like said above don't hammer it going around corner's and drive respectful and all will be good.

All of this is good information. I am planning on upgrading my 8.75 with a Dana, I'm not afraid of a spool in the rain, but parking and pushing a heavy B body (4000lbs) is hard enough with manual steering and a tight Sure-Grip. Would a spool be that much worse?

HAHAHAHAHAA!

YES!

I expect soon replies here stating about my rights to run a spool, road race cars that seldom if ever run a spool because they turn LEFT and right, complaints about other members hoping others with spools on the road wreck, and avoiding like the plague, with huge doses of deflection of physics, as already mentioned, fact that a spool causes/promotes rear tire loss of traction in a turn, unless running stagger or lifting a wheel, and most of all, only those who are brave and got big ones drive a spool on the road in the rain, so be a man get spooled.,

Surprised anybody that survived their spool wreck, can read this in the ICU.

I have a vague memory of a locker controlled by air pressure, so it can be turned on and off from the dash. Or am I just mixing up memories?
Anyway if it exists, it doesn't seem to dominate the market. Must be a reason for that.

ARB air locker. I recall seeing them in the 4WD magazines.

Winner !!

Just put your purse down before you park and you will be ok! LOL kidding, parking lots are really the spools biggest downfall.

My Locker does not slip a tire on turns or wet roads as it unlocks one tire that just goes along for the ride when turning. Of course it locks back up when you straighten out. I have driven in the rain with my locker 3 times when I have got caught in the rain and that on my 30 x 9 slicks. I just took it easy and had no problems. I agree a posi/sure grip may slip a tire that uses a clutch pack but my locker unlocks mechanically as it dont use clutches that need to slip on turns, Ron

I installed one of these Posi units in my Dart over the winter https://www.jegs.com/i/JEGS/555/62820/10002/-1.

Seems okay to drive but its noisy when turning. Even slight turns you can hear it.

Maybe it'll break in a bit and not be so bad but It creeps me out, I wish I had just gone with a spool now.

My experience is much like 383Man's with his locker. I've had both a Detroit Locker with a manual trans and a spool with a 727 and I could live with either one just fine. The locker was behind a T56 in a 9". The only time that one behaved oddly was if you were letting off the gas in a turn (which isn't a great idea anyway). It would clunk and shimmy just a bit. With any type of reduced tread depth tire and some moisture on the road, you just need to take it easy. The locker is more expensive so that's a downside, but it's very true that the spool is absolutely no fun to push the car around when it's not running. Just my 2 cents