Re: Is a ford 9\" in a SWB Jeep as bad as some people lead on?????
I put a 9" from an Early Bronco in my CJ7 a couple of years ago. TeamRush, you wanted the info on the swap so here's how I didi it. The swap went pretty easy, as the new spring perches ended up being located right under the stock ones (77 CJ7, 74 Bronco 9"). I left the perches there in case I ever want to do a spring-over. Since I needed to weld on the spring perches, I could "aim" the pinion the way it needed to be for proper driveshaft angle. What you need to do is, using an angle-finder, measure the angle of the yoke at the output of the transfer case with the jeep on its wheels and the driveshaft off. Put the tranny in neutral and turn the yoke until it's vertical. Then jack up the jeep, pull out the AMC 20, slide in the 9" and the spring perches, kind of eyeball the yoke as to where the yoke was from the old one and tighten up the u-bolts. Put the wheels back on and set the jeep down. Measure the angle across the pinion yoke with the angle finder, figure out about how much you need to move it in which direction. Jack it up again. loosen up the u-bolts (you do't need to take the tires off) and twist the whole assembly. Tighten the u-bolts, lower and re-measure. After a couple of times, you'll get them to match. Tack weld the perches and jack it up, take the tires off and take the u-bolts off. Lay in your best weld.
When I put mine in, I also relocated the shock mounts to the axle tube and got rid of the whole spring hanger. I kept bending the studs for the shocks on them anyway. I used the spring plate from the Bronco. The biggest problem was that the 9" is a whole lot shorter than the AMC 20. I was running the stock T150, and I ended up with a new driveshaft. A year later, when I swapped in the T18 (I'm turning my CJ7 into a Feep) I was able to re-use the origional rear driveshaft. I never ran one with a CV joint, probably because I got the angles to match. I have never had a problem with the low pinion causing vibration problems or clearance problems. Here in Wisconsin, we have mud, stumps, branches, logs and occasional loose rocks that grab things that hang too low (thus my bent shock mounts on the spring hangers). I don't see any drawbacks to the conversion. Disc brakes are right around the corner for me, and I put a spool in 2 weeks ago (only took a couple of hours) for the ultimate in traction. Funny, it squeals now every time I go around a corner.
