Rear Pinion Bearing
01-08-2012, 01:18 AM
#1
Junior Member
Thread Starter
Join Date: Feb 2008
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Rear Pinion Bearing
I've got a 2002 F150 FX4 (170k) that I believe has an issue with the rear axle. I've noticed a low hum/whine coming from the rear axle for a while and have also some seepage coming from the front of my pinion seal. The noise increases with speed and it goes away when i am coasting. From what I have read this is likely the wear on the pinion bearing due to the slow leakage of the rear axle fluid.
I have read some posts on re-setting the bearing preload, but is there a point at which this will not work and the differential needs to be rebuilt? Is it possible to not be able to achieve the MIN pre-load of 8-14in-lbs indicating a bearing that is too worn?
I was hoping to set the preload, replace the seal and put fresh fluid in. I might also replace the wheel bearings.
I have read some posts on re-setting the bearing preload, but is there a point at which this will not work and the differential needs to be rebuilt? Is it possible to not be able to achieve the MIN pre-load of 8-14in-lbs indicating a bearing that is too worn?
I was hoping to set the preload, replace the seal and put fresh fluid in. I might also replace the wheel bearings.
01-08-2012, 05:38 AM
#2
Senior Member
If you have a bad pinion bearing, the rearend has to come apart anyway. You gotta pull the pinion shaft, and to do that, you have to pull the carrier.
Is there any movement (in/out/ side-to-side) of the pinion shaft?? Pull the cover and take a look around in there first. Does the carrier move left or right at all?
Typically, you can reset the pinion preload as long as you go "at least" as tight as it was before. You do this when you replace a pinion seal. Before you remove the pinion nut, you use a torque wrench to check the rotating resistance of the pinion, and when you put it back together, you tighten it until it reaches that resistance again. Easy to do, but hard to explain.
Is there any movement (in/out/ side-to-side) of the pinion shaft?? Pull the cover and take a look around in there first. Does the carrier move left or right at all?
Typically, you can reset the pinion preload as long as you go "at least" as tight as it was before. You do this when you replace a pinion seal. Before you remove the pinion nut, you use a torque wrench to check the rotating resistance of the pinion, and when you put it back together, you tighten it until it reaches that resistance again. Easy to do, but hard to explain.