Pinto Car Club of America

Well,
I finally got my Mustang II 8" rear bolted in. Yes it was a pretty easy swap. I noticed that it pushed my driveshaft a little farther into my T5, but still has about 1/2" to 3/4" clearance, and doesn't touch the tail housing of the trans. I filled it up with gear oil, fired it up and this thing sings a high pitched whine, louder and higher as the rpm's increase. The only thing I did to this rear was change the pinion seal and was careful not to overtighten the pinion nut (which was not very tight when I took it off). Have any of you had a singing rear like this. It kinda goes SSHHEEEEEEEEE and when you let it slow back down it's like a SSHHeeeeowwwww. Pinion bearing worn out? Obviously the rear was used, so I had no idea if it had any problems or what kind of mileage is on it. I need to have this thing up and running for Knotts in April.
Joe

Joe ,
There is a non-reusable Crush sleeve in the Pinion shaft bearing area that must be replaced when you loosen the Pinion nut for any reason. The Crush amount is linked to the tightening torque, so the Nut might not have felt tight when you removed it. Re-tightening the nut would overload the pinion bearings and cause the squeal. Pull the center section and do a bench rebuild or have a rear gear shop do a reset and lash adjust with new crush sleeve.  Time for Limited slip too?

Good luck ..

Pintosopher

I'm pulling the third member today and having it rebuilt. The guy says it shouldn't be too bad. I definitely wasn't going to run it anymore until it was fixed. I didn't want metal parts flying around in there!!

Joe

Well, as I suspected the differential guy found bad pinion bearings in the rear, so about $150 will solve that problem.