Hi ok heres the deal i have a 70 440 6bbl Cuda with a 8 3/4 rearend . i have 4 center carriers for it 2 are nonposi units with 3.23 gears and 2 are suregrips units with 3.23 and 4.56 gears. when i run the nonposi 3.23 it works fine no problems but when i put the suregrip units in the rearend it will not move forward it will back up but thats it. when i put it up on jackstands the wheels will turn forward under power but when its on ground nothing. the rear has super stock springs moved in 3 inches per side and a 69 roadrunner house because its a few inches narrower . but like i said it only does this with the suregrip units in it . Have any ideas what may cause this ???
Sep 21, 2011 at 2:14 PM

