Axle assembly having a drive pinion support bearing and a method of assembly

1. An axle assembly comprising:

a drive pinion that is rotatable about a first axis, the drive pinion having a drive pinion passage that extends around the first axis and through the drive pinion;

a through shaft that extends through the drive pinion passage and is rotatable about the first axis; and

a support bearing that is disposed in the drive pinion passage and that rotatably supports the drive pinion, wherein the through shaft further comprises a through shaft shoulder that engages the support bearing to inhibit axial movement of the support bearing with respect to the through shaft.

2. The axle assembly of claim 1 wherein the support bearing extends continuously around the through shaft and extends from the through shaft to the drive pinion.

3. The axle assembly of claim 1 wherein the drive pinion has an inner drive pinion surface that defines the drive pinion passage, wherein the support bearing inhibits bending of the inner drive pinion surface toward the through shaft.

4. The axle assembly of claim 1 wherein drive pinion includes a gear portion and a shaft portion that extends from the gear portion, wherein the gear portion has a set of teeth that are arranged around the first axis and that are disposed opposite the drive pinion passage and the support bearing is disposed in the gear portion.

5. The axle assembly of claim 4 wherein the gear portion has a first gear portion end surface that is disposed at an end of the drive pinion and a second gear portion end surface that is disposed opposite the first gear portion end surface, wherein the support bearing is axially positioned between the first gear portion end surface and the second gear portion end surface.

6. The axle assembly of claim 1 wherein the drive pinion further comprises a drive pinion shoulder disposed in the drive pinion passage, wherein the drive pinion shoulder engages the support bearing to inhibit axial movement of the support bearing.

7. The axle assembly of claim 6 wherein the drive pinion has a gear portion that has a first gear portion end surface that is disposed at an end of the drive pinion, a second gear portion end surface that is disposed opposite the first gear portion end surface, and a set of teeth that extend from the first gear portion end surface to the second gear portion end surface, wherein the drive pinion shoulder and the support bearing are axially positioned between the first gear portion end surface and the second gear portion end surface and the drive pinion shoulder inhibits axial movement of the support bearing toward the first gear portion end surface.

8. The axle assembly of claim 1 wherein the through shaft shoulder and the support bearing are disposed inside a gear portion of the drive pinion.

9. An axle assembly comprising:

a drive pinion that is rotatable about a first axis, the drive pinion having a drive pinion passage that extends around the first axis and through the drive pinion and a drive pinion groove that extends from the drive pinion passage and away from the first axis;

a through shaft that extends through the drive pinion passage and is rotatable about the first axis; and

a support bearing that is disposed in the drive pinion passage and that rotatably supports the drive pinion, wherein the drive pinion groove receives a retention feature that extends into the drive pinion passage and inhibits axial movement of the support bearing.

10. An axle assembly comprising:

a drive pinion that is rotatable about a first axis, the drive pinion having a drive pinion passage that extends around the first axis and through the drive pinion;

a through shaft that extends through the drive pinion passage and is rotatable about the first axis, the through shaft having a through shaft groove that extends toward the first axis; and

a support bearing that is disposed in the drive pinion passage and that rotatably supports the drive pinion, wherein the through shaft groove receives a retention feature that extends into the drive pinion passage and inhibits axial movement of the support bearing.

11. The axle assembly of claim 1 wherein the support bearing is a roller bearing assembly.

12. The axle assembly of claim 1 wherein the support bearing is a journal bearing.

13. An axle assembly comprising:

a drive pinion that is rotatable about a first axis, the drive pinion including:

a gear portion that has a set of teeth, a first gear portion end surface that is disposed at a first end of the drive pinion, and a second gear portion end surface that is disposed opposite the first gear portion end surface;

a shaft portion that extends from the gear portion and has a shaft portion end surface that is disposed at a second end of the drive pinion that is disposed opposite the first end, wherein the shaft portion extends from the shaft portion end surface to the second gear portion end surface; and

a drive pinion passage that is defined by and extends through the shaft portion and the gear portion, wherein the drive pinion passage is coaxially disposed with the first axis;

a through shaft that extends through the drive pinion and is received in the drive pinion passage, the through shaft being rotatable about the first axis;

a first support bearing that is disposed in a portion of the drive pinion passage that is defined by the gear portion and that rotatably supports the drive pinion, wherein the first support bearing inhibits deflection of the gear portion with respect to the through shaft; and

a second support bearing that is disposed in a portion of the drive pinion passage that is defined by the shaft portion and that rotatably supports the drive pinion, wherein the second support bearing is axially positioned midway between the shaft portion end surface and the second gear portion end surface to inhibit deflection of the shaft portion with respect to the through shaft.

14. The axle assembly of claim 13 wherein the first support bearing is spaced apart from and does not engage the second support bearing.

15. The axle assembly of claim 13 wherein a retention feature is disposed in the drive pinion passage and inhibits axial movement of the first support bearing.

16. The axle assembly of claim 13 wherein a retention feature is disposed in the drive pinion passage and inhibits axial movement of the second support bearing.

17. An axle assembly comprising:

a drive pinion that is rotatable about a first axis, the drive pinion having a first gear portion end surface that is disposed at an end of the drive pinion, a shaft portion end surface disposed at an end of the drive pinion that is opposite the first gear portion end surface, and a drive pinion passage that extends around the first axis and through the drive pinion from the first gear portion end surface to the shaft portion end surface;

a through shaft that extends through the drive pinion passage and is rotatable about the first axis; and

a support bearing that is axially positioned in the drive pinion passage between the first gear portion end surface and the shaft portion end surface, wherein the support bearing rotatably supports the drive pinion and the support bearing engages only the drive pinion and the through shaft.

18. The axle assembly of claim 17 wherein the drive pinion has a drive shaft shoulder that engages the support bearing to inhibit axial movement of the support bearing with respect to the drive pinion.

19. The axle assembly of claim 17 wherein the through shaft has a through shaft shoulder that engages the support bearing to inhibit axial movement of the support bearing with respect to the through shaft.

20. The axle assembly of claim 19 wherein the drive pinion has a drive shaft shoulder that engages the support bearing to inhibit axial movement of the support bearing with respect to the drive pinion.