1980 cobra 4th rear end. First 3 where 7.5. The current one (4th) is a 8.8 from an 89 GT. 410 gears new carbon clutches freshened up everything else. Did the break in period and it is starting to hum, just like all the others did in the beginning. It's for a 302 big can bored 60 intake and carb with t5 my 300 to 325 hp nothing crazy. But I'm scared it'll go out just like the others because it's now humming. Any help would be appreciated. My Trans mount and motor mounts are bad.