I have 70 cutlass S that has a 2.56 anti-spin rear. The car came with a 350 2bl. It now has a 455 4 bl. I do not beat on the car. Burn outs here in there but never have done donuts or anything like that. I don’t race the car just cruse. I’m have an issue with it rite now. When I make right turns it’s making a clicking sound at the Driver side rear axle. I pulled the tire and drum to take a look. The axle move ever so slightly in and out. It make a noise when I do this at the end of the axle. Like a little bump. I’m not sure if I have a c-clip or an O-axle. I did change the dif oil in February. I did put the GM additive. If someone could let me know if this is an easy fix. It maybe a axle bearings? I appreciate any help.

 

That is a Type O rear end. Original to a 1970 Cutlass or 442. There are no C clips it has bolt in axles. Could be a axle bearing making noise or the posi. New posi additive is not as good as original type of fluid.