I have a 62 chev 1 ton panel with a ho 72 rear end. I've tried a number of different 3rd members to try to eliminate a whine from the rear that happens when the engine is working hard, the harder it works the louder it whines. When I back of the gas the whine decreases . I'm not sure if this is normal but accentuated by the fact it's a panel letting the noise resonate in the empty space in back.
I've had one 3rd member checked by a shop , who reported all was well with the unit, and spun the 2 others I tried while on the work bench and could hear nothing weird, even using a stethoscope .
I've tried deep purple rear end oil as well as conventional 80 weight with assorted mixtures of Lucas oil treatment. When the rear end was out I checked the wheel bearings as well and all was well there. None of these rear ends are positrac. I don't think it the tranny , a t 5 as the whine increases as I go through the gears.
Any input would be appreciated .
Thanks John
