07 6.7 4x4 rear pinion seal leaking?

[Whiteranch04]

I just noticed my 2007 3500 with the 6. 7 and 86,000 thousand miles is leaking slightly below the rear diff pinon yoke seal area. I just spotted it and checked the level and it was about 1/2 inch low. Looks like I caught it before it ran dry, I had just been thru a really muddy ranch road and got high centered on the rear end. I had to pressure wash it before I could try to see if anything was wrapped around it like baler twine or wire or somekind but it got to dark and will start in the morning. I ordered the rear pinion seal from a local parts store, it will be in by 7am in the morning and am going to pull it and replace it and pray that the pinion bearings are not out as well. Does anybody know what size the pinion nut is and what is the torque speces on it and know of a how to link on remove and replace the rear diff pinion seal?? I have changed out the rear end lube 2 times since new and am praying that the rear end is not shot. Thanks for any info comments etc, I sure hope the seal is correct I have coming in, the dealer is 130 miles one way and this is my only truck. Anybody replace there seal in a 2007 single wheel with 6. 7 and six speed??? What size is the nut and how do you do it according to the book? Where can i find this info?? Is there an online manual procedure somewhere i can read up on tonight?? Thanks!

 

[sag2]

Is it leaking or just weeping a little oil on the case? Unless it is dripping I would not change it if you don't know what your doing or don't have the tools. Not sure of the nut size, but you should always replace the nut. If not make sure you have lock-tite. Also if using the old nut, mark it in relation to the pinion (small chisel or punch mark on nut and end of pinion) so you can reinstall the nut to the same position plus 1/16 turn. Go too far and you ruin the (crush sleeve) bearing preload, too little and not enough preload. You will need a puller to get the yoke off, and you can then pry the old seal out. You also need a yoke holder to hold the yoke from turning while removing and installing the nut. If you use a new nut you need a dial inch pound torque wrench to set the preload. It isn't a hard job, but if you don't do it right you will do far more damage than you have now. Weigh the cost/benefit of adding some fluid now and then vs. fixing it tomorrow and maybe having to replace the ring and pinion down the road because it wasn't done correctly.

In any case, here is the SM procedure assuming you have all the correct parts and tools.



Removal

1. Remove axle shafts.

2. Mark propeller shaft and pinion flange for installation reference and remove shaft.

3. Rotate pinion gear three or four times.

4. Record pinion torque to rotate (1) with an inch pound torque wrench (2).

5. Hold pinion flange (1) with Wrench 8979 (2) and remove pinion flange nut and washer.

6. Mark a line across the pinion shaft and flange for installation reference.

7. Remove pinion flange (1) with Puller 8992 (2).

8. Remove pinion shaft seal with a pry tool or slide hammer mounted screw.



Install

1. Install new pinion seal with Installer 8896 (2) and Handle C-4171 (1).

2. Apply a light coat of teflon sealant to the pinion flange splines.

3. Install flange on the pinion shaft with the reference marks aligned.

4. Lightly tap the pinion flange onto the pinion until a few threads are showing.

5. Install flange washer and new pinion nut.

6. Hold flange (2) with Flange Wrench 8979 (1) and tighten pinion nut until pinion end play is taken up.

7. Rotate pinion several times to seat bearings.

8. Measure pinion torque to rotate (1) with an inch pound torque wrench (2). Pinion torque to rotate should be equal to recorded reading plus an additional 0. 40-0. 57 N·m (3-5 in. lbs. ).

9. If torque to rotating is low, tighten the pinion nut in 6. 8 N·m (5 ft. lbs. ) increments until pinion torque to rotate is achieved.

10. Rotate pinion several times then verify pinion torque to rotate again.

11. Install axle shafts.

12. Install propeller shaft with reference marks aligned.

13. Check and fill differential if necessary.