04 XLT rear end whine

[ericsauvage08]

All right, Gents, i have fallen victim to the notorious X rear end whine. Both hub bearings are good and after reading lots of these threads, liiks to be the ring/pinion. I plan to swap the fluid to the 75w140 for a temp fix, but will eventually be looking to swap the parts. Without confirming which kit i need for sure, i think it is part #5L3Z-4209-B, from the TSB for the 8.8/3.55 ratio. In any case i googled the number and didnt find any sellers, so i have the following questions:

1. Have the part/kit #s changed?
2. How long do you imagine i can go without getting serious about fixing this? ( probably has 20+k miles with the noise.
3. Would bad suspension/brakes cause the r/p to go bad?
4. If no more kits, I'm wary of a junk yard pull, any fixes to replace seals or bearings that may stave off the inevitable?
5. If fixed with that kit, do you imagine ill eventually have the same problem again at some point?

Any other input from you Vets put there? THANKS so much for all responses!

 

[imp]

All right, Gents, i have fallen victim to the notorious X rear end whine. Both hub bearings are good and after reading lots of these threads, liiks to be the ring/pinion. I plan to swap the fluid to the 75w140 for a temp fix, but will eventually be looking to swap the parts. Without confirming which kit i need for sure, i think it is part #5L3Z-4209-B, from the TSB for the 8.8/3.55 ratio. In any case i googled the number and didnt find any sellers, so i have the following questions:

1. Have the part/kit #s changed?
2. How long do you imagine i can go without getting serious about fixing this? ( probably has 20+k miles with the noise.
3. Would bad suspension/brakes cause the r/p to go bad?
4. If no more kits, I'm wary of a junk yard pull, any fixes to replace seals or bearings that may stave off the inevitable?
5. If fixed with that kit, do you imagine ill eventually have the same problem again at some point?

Any other input from you Vets put there? THANKS so much for all responses!

1. Unknown
2. Has noise level increased recently, or stayed pretty constant? 20K with noise mostly rules out failing bearings on axles OR in the center section, especially PINION bearings. Slight misalignment of r/p set-up can hum for 100K without real harm done.
3. Absolutely not.
4. Not sure what kind of "kit" we would be talking about. The only expendable parts usually replaced by "kit" are clutch plates for limited-slip. One rips a center section open, if unsure of exact cause, starts examining for issues, then replaces parts as needed.
5. Cannot answer that effectively.

If it were mine, and noise was worsening, I would attempt through use of a stethoscope, to pinpoint location of noise production with vehicle up on stands and running in Drive. If 4X4 AUTO equipped, this cannot be done without first disconnecting power to the transfer case clutch. (easily done), OR running in 4X4 HIGH (more easily done). A stethoscope can be a length of 3/8 inch I.D. rubber hose held to area under pinion shaft, axle hubs, and sides of center section where axle shafts enter, other end stuck in your ear. Noise will be most pronounced closest to the source. I was certain my noise was r/p related, but the steth. revealed this:

Outer race of one hub bearing, L.H. side, galled in center of raceway only, thus allowing rollers to still roll over the two areas adjacent tpo the pitting. Drove with noise for over 5K miles, before finally getting scared enough to look for the cause. Defining the cause in advance can save a helluva lot of headaches and money! imp

 

[icepickjazz]

I know this thread is getting to be be old. You have to purchase the parts individually rather than in a kit.

For the clutch pack TSB you need part# 6L1Z4947B, 7L1Z4A109C, W710084S439, 1L2Z4B422BA, F3TZ4121AA, you'll also need the gear lube and friction modifier from Ford.

For the ring and pinion TSB you'll need part# 8L3Z4209N, 2 part# XW4Z4221AA, 2 part# D9AZ4222A. Just contact the guys at what was formerly known as tousley ford parts. http://parts.autonationfordwhitebearlake.com/