Device and method for aligning the rear wheels of an automobile

A method for aligning an automobile's rear wheel to include differential housing brackets, the automobile having leaf springs, a differential housing, a passenger's side differential housing bracket, and a driver's side differential housing bracket, the method comprising the steps of:

• separating at least one leaf spring from a differential housing of the automobile;
• removably securing a first plate to at least one of the leaf springs of the automobile, the first plate having a substantially smooth, continuous lower surface and a smooth upper surface, the upper surface including a pair of substantially parallel rails extending upwardly from the upper surface;
• removably securing a second plate to an associated one of the differential housing brackets of the automobile, wherein the second plate has a substantially smooth lower surface;
• positioning the first plate on top of the second plate so that at least a portion of the lower surface of the upper plate is received between the rails, wherein the substantially smooth upper surface of the lower plate is in face-to-face contact with the lower surface of the upper plate;
• adjusting the position of the first plate relative to the position of the second plate along a longitudinal axis of the automobile while the plates are in face-to-face contact and while the plates bear the weight of the automobile;
• and
• permanently securing the first plate to the second plate, thereby rendering the plates nonadjustable.

A rear-wheel alignment device for an automobile having an axle, a leaf-spring, a centering pin on the leaf spring, a differential housing, and a differential housing bracket defining an aperture configured to receive the centering pin, the device comprising:

• a first plate removably secured to the leaf spring, the first plate having a substantially continuous bottom surface and a smooth upper surface, the first plate including a pair of substantially parallel rails connected to and extending upwardly from the upper surface of the first plate, the rails being spaced apart and extending the entire length of the first plate, the rails and the upper surface defining a channel, the first plate also defining an aperture passing through the upper surface configured for receiving the centering pin on the leaf spring;
• and
• a second plate having an attachment pin extending from an upper surface of the second plate, the attachment pin shaped to be received in the aperture defined by the differential housing bracket, the second plate also having a substantially smooth lower surface that is in face-to-face contact with the upper surface of the first plate, thereby forming an area of contact between the first plate and the second plate, the lower surface of the second plate being at least in part received within the channel such that the second plate is constrained for infinitely adjustable linear movement between the rails and along the entire area of contact within the channel when the upper surface of the first plate is in contact with the lower surface of the second plate such that the weight of the automobile may be transmitted between the first and second plates, the surfaces being sufficiently smooth to permit adjustment of the plates relative to each other while bearing the weight of the automobile, the second plate being removably secured to a differential housing bracket of the automobile, the first plate being welded to the second plate after the plates are adjusted relative to each other.

A method for aligning rear-wheels of an automobile to include a differential housing bracket, the automobile having an axle, leaf-springs, a centering pin on the leaf spring, a differential housing, and differential housing brackets, each bracket defining an aperture configured to receive the centering pin, the method comprising the steps of:

• separating at least one leaf spring from a differential housing of the automobile;
• removably securing a first plate to the leaf spring of the automobile, wherein the first plate has a substantially smooth, continuous bottom surface and a smooth upper surface, the first plate also including a pair of substantially parallel rails connected to and extending upwardly from the upper surface and along the entire length of the first plate, the rails being spaced apart, the rails and the upper surface defining a channel, the first plate also defining an aperture passing through the upper surface configured for receiving the centering pin;
• removably securing a second plate to a differential housing bracket of the automobile wherein the second plate has an attachment pin connected to an upper surface thereof, the attachment pin shaped to be received in the aperture defined by the differential housing bracket, the second plate also having a substantially smooth lower surface;
• placing the lower surface of the second plate in face-to-face contact with the upper surface of the first plate, thereby forming an area of contact between the first and second plates, the lower surface of the second plate being at least in part received within the channel such that the second plate is constrained for infinitely adjustable linear movement within the channel and between the rails along the area of contact when the upper surface of the first plate is in contact with the lower surface of the second plate such that the weight of the automobile may be transmitted between the first and second plates, the surfaces being sufficiently smooth to permit adjustment of the plates relative to each other while bearing the weight of the automobile;
• maintaining the plates in contact;
• adjusting the position of the first plate relative to the position of the second plate along a longitudinal axis of the automobile while the plates are in contact and bearing the weight of the automobile;
• and
• welding the first plate to the second plate without first removing the weight of the automobile from the plates, thereby rendering the plates non-adjustable.