What are their HP/Tq limitations, and which would be the better choice in a 95% street driven car...408/4-speed A-body? The price is pretty similar, so dollars aren't really a factor.

Thanks for the input guys!

I had a truetrac in a 4200 lb dakota pick-up with a stroker 383 that was making 535 ft lbs of torque, shifted with a TKO transmission, and never had a problem with it. I prefer the truetrac over a locker because going around corners is very smooth, no ratcheting action like you get with a locker.

when you get into the throttle and "set" the truetrac, it locks up just like a locker does, but when there's very little throttle input, and/or nearly zero traction, it acts like an open diff, in fact, if you jack up the rear and spin a tire, the opposite side will spin backwards, just like the open diffs, it does this because there's no load on the gears inside the differential.

I also like the truetracs because they don't have clutches that wear out

A Detroit Locker can be annoying to drive on the street because of the excessive internal lash.

As I've been reading about the Truetrac, I like the design and principles of it...just want to make sure I'm not going to grenade the thing dumping the clutch, etc...

I use a Detroit Locker in my 63 and it has been in the car about 5 years. I myself like it as in normal driving I dont even notice it. But it will make some noise sometimes when locking back up after making a turn or getting into it before the car is straight and the diff has locked both wheels. I have run 10.70 with it and no problems. Here is a vid I found about it. I dont know much about the True Track as I have never used it but since I use a Detroit Locker I thought I would tell you about it. Ron
http://www.youtube.com/watch?v=FYBOoljH-qE&feature=related

Thanks Ron. Gives me more info, for sure. I'm not sold on either unit, but in looking for a Mopar SG unit (preferably clutch type) I'm finding that I might be just as far ahead to buy a new unit from Detroit...especially when I factor the possibility of having to rebuild a used unit shortly after installing it.