F53 Output Shaft Assembly failure
Extreme vibration suddenly set in with a ferocious roar at speeds above 45mph while traveling down I-95 South. Discovered five of seven bolts were out of the emergency brake assembly at the transmiss...
Forum Discussion
centerline wrote:
yep.. its common. it happens when the oil leaks out. it gets filled independently and holds its own oil and is NOT shared by the rest of the transmission, as some people think.
you will be a very, very lucky person if you can get it apart without removing the transmission...
what usually happens is, where the brake/tail-shaft sleeves over the thru-shaft of the transmission inside that brake pod assembly, when it runs dry of oil, the bearings will overheat so severely that it softens the shafts so they have a tendency to either twist a little, or otherwise, effectively weld themselves together...
on yours, the bolts may have came loose and let the oil out, or the loose bolts could be a symptom of the vibration after the bearings went... but the most common reason for this failure is... people forget to disengage the parking brake and it creates the heat, and the oil gets so hot it loses its lubricating properties, and then the bearings take over and create EXTREME heat.... the first indication is when the speedo stops working (as the nylon gear melts), and if one knew what this indicator meant and would stop then, the brake pod may be able to be salvaged..
if you can not slide or pry the pod section off the back of the tranny, it will have to be destructivly cut off (which requires removing the transmission), and after removal, you will then need to have a new thru-shaft put in the transmission...and find a new parking brake pod assembly to install.
the particular assembly you need is the one that was also used in an F-550, as it is the ONLY one that connects properly to the driveline, and has the correct speedo gears in it...
X2 WOW! centerline knows his stuff.......
Richard
