After all my time working with Ts, it seems that some driveshaft pinion sleeves have held up very well, while others have cracked or even disintegrated. Mine looked so good that it appeared to be a machined part of the drive shaft. Not only did it show no cracks, chips, or any damage, it still measured well within tolerances. However, we tore down my friend's "rebuilt" differential, and we found that the sleeve was severely cracked and had almost fallen apart.
Does anyone have any insight as to why this is? Maybe Ford used different recipes or manufacturing techniques for the metal throughout production due to cost and/or availability?
If someone has used heat to install the drive shaft sleeve, they may have exceeded the temperature that was needed and caused the structure of the steel to change making it more brittle.
Where as the ones that survived, were just pressed or pounded on.
Wouldn't too much heat anneal the steel and make it softer?
The drive shaft sleeves are an accident waiting to happen - they can and do crack from metal fatigue after many years of use.
Anybody without external accessory brakes would be more safe with at least a lined emergency brake and by keeping himself trained to use the emergency brake if something in the drive line fails.
Fun Projects accessory bearing is a good replacement: http://www.funprojects.com/products/2587e1.cfm