Do I need to put a spring in the U-Joint? Pro's Con's? And How much play should I have 3/8 or 5/8?

Thanks

Bill

There really is no pro or con for or against in my opinion. The spring takes up space, but still allows float. We like it just because it controls the shaft while the car goes through it's travel.

Normally w/out a spring we cut the driveshaft to allow a 1/4" of float.

With a spring we still have the 1/4" but we collapse the spring and cut that additional amount off.
Say the collapsed length is 1/2", then that is added to the 1/4" and the total is 3/4".

Once you commit to the spring though, you have to always make sure that it is in there after servicing. If not, the driveshaft will probably be too short and will slip out of the yoke or coupler and tear up one or the other.

I agree with most of what Scott has said except for the Pro's and Con's. It really depends on what spring you run. There are real stiff ones and real soft ones. I have seen instances of the stiff spring being too stiff and not letting the car work right. Much like if the driveshaft is too long.

Some may say I am full of it, but I have seen a car go from being a turd to really hooked up and the only thing changed was removal of the stiff spring.

If the drive shaft bottoms out the car will handle like crap,so you may just have something there...I learn something new every day .thanks

Where do you buy softer springs?Thanks

He is so right. If you are having handling problems, take the spring out. Put the deal together without the torquetube and without the torsion stops on, put a 1" socket on the jack and jack the rear-end up to ride height and move(rotate) the axle ALL the way through the motion. You'll discover amazing things by doing this.
E-mail me if you need more detail.
cwh10@chrysler.com

I agree with scott 100 percent.. because there are so many other things you can do to make that car work for, or against you other than the Drive shaft.. If its cut for the spring or not correctly, either will work.. and for you to say the spring alone made the difference is kinda iffy.. First you mean to tell me, you actually took the drive line apart and put it all back together and got the same track conditions is silly.. and if you did.. What clicked to tell you man, the shocks are perfect, the wheel spacing is perfect and all the other adjustments were perfect so damn the spring in the U joint must be the problem???? NOW, maybe you should go to cup bro.. Not trying to ruffle feathers but Scott got it right on the head..

Well, let me see here. We ran 12 shows with the stiff spring in and the drive shaft was cut to the proper length. The car would never work once the track slicked off. We tried our standard adjustments and many other things to try and get the thing to hook up. We checked the drive line for length again and while doing so replaced the stiff spring with a softer one. Just stiff enough to keep the drive shaft pushed back into the rear coupler. After that switch the car would work on heavy or dry slick tracks and our standard adjustments actually made a difference.

If you think the stiff spring wasn't the problem then more power to you. I believe it did make the difference and will never run the stiff spring again.

BTW, Scott and I are good friends and have talked about this at great length.

I re read my post.. So i figured i would add a part.. 1 being, it came off rude, and that was not my intention.. I was simply stating that when i cut my drive shaft, if i wasnt 110 percent sure that it was correct then i would call someone who knew Exactly what needed to be done.. Now with that said.. If i hadnt done that.. I would work on shocks, spacing and set up period.. and the "other" possible chassis adjustments.. Just felt it was odd the way said that.. Sry for the confusion

Another thing to think about between weak or strong spring is that you are pushing against the thrust surface of the main bearing. Anyone who has bottomed a drive shaft can tell you what the thrust bearing looked like at tear down.