Bolt in bottom of bell housing

[sam cooper]

Could someone tell me the purpose of the small bolt running from side to side in bottom of bell housing? Sam Cooper

[E.Moore]

If the small bolt is about 1/4" that you see in the bottom of your bell housing, someone removed the Radius Rod Ball Cap Pin and installed the bolt. The radius rod ball is held to the bell housing with two bolts that have a slotted head for the pin to keep the bolts from turning when the radius rod ball nuts are tightened or removed. On many bell housings, the up and down motion of those bolts from normal driving, will wear the surface that the slotted head sits on, to the point that the pin no longer holds the bolts from turning, making it a difficult job to remove the front end for repair of the front axle. When those bolts turn with the nut, the bell housing has to be removed and the worn surface welded up, then refaced, or shims can be added to the worn bell housing surface to get the radius rod bolt back to its original height. If shims are used, they must be hardened, or they will come apart with the pounding that takes place under normal driving conditions. The radius ball needs to be as round as possible because when the ball caps are tight, this sets the caster for the front end. The more the radius ball is worn, the radius ball is constantly moving up and down and back and forth, resulting in uneven steering. The less caster the front end has, the steering tends to be stiffer, especially coming out of turns. Front end shimmy is caused not only from worn out tie rods and drag links, but from excessive motion at the radius ball along with worn tie rods and drag link ends.