A few front diff questions

[Alwayssideways]

Hi All,
I dont post much. I normally just troll for info when needed. Now After going through a few threads I need some help with a current problem I am having with my 2003 ST.

I had changed the front hub bearings a few month ago. At the same time they had just paved my road. After getting the bearings done driving down the road I heard a louder than normal road noise. I contributed it to the grippy AT 32" I have on the truck due to it really only got "really noticeable" on my freshly paved road. Well the past few times taking the truck out I had smelled what I thought was something like hot plastic. I didn't think much of it since the operating temp of the truck was fine and the truck was running well.

Fast forward to today. I noticed a small (about golf ball sized ) puddle under the front axle of the truck . Smelled it, and it was gear oil. I looked under the truck and saw the front diff was wet. So I figured it was the diff cover, but researching more and more it sounds like my pinion bearings are shot . My evidence which match symptoms from other posters with bad pinion bearings. Leaking diff, specific sound (confirmed on you tube to match the "road noise" I have now, the fact the diff is heating up and causing a hot plastic smell.

I haven't gotten to get under the truck to see if there is play in the bearings yet. It is night time and I will look at it in the day light tomorrow. I am just preparing myself for a few scenarios if needed.

1. how hard is it to remove the front diff?
2. Roughly what would a trans shop charge to replace the bearings (if I take the diff off and leave it with them)?
3. Can the truck be temporary be made 2w drive while I save up for or wait for the diff to get rebuilt? (i.e remove diff, axles and drive shaft)

Any help would be appreciated.
Thanks

 

[crankyjew]

As far as I know, it's not hard to pull the front axle/diff. Three big bolts I think, and pull the CV and drive shafts.
I would expect a few hundred dollars for a shop to replace bearings, given whats involved. Most shops should be willing to work something out with you if you leave the axle and you're not in a hurry....
I wouldn't see any problem with a temporary 2WD setup...
I bumping this thread hoping that other more knowledgeable members will chime in...

 

[vroomzoomboom]

if you know what your doing you can have the front diff out in 45min to a hour (i have done it, that is out, not out and back in). you have to separate the upper ball joint/control arm from the spindle (one nut and bolt, i believe is a 13mm and a 15mm), remove your brake caliper (2 15mm bolts you will pull the bracket and caliper out in one shot), undo the axle nut thats in the center of the rotor (32 or 34mm cant remember off the top of my head), push the axles out of the wheel bearing (that can be a little tuff sometimes, but it is do able) then wiggle the axles out of the diff. then there are four bolts for the front drive shaft (25 torx if i am not wrong), and three holding the diff itself ( all 3 are 13mm, one on the passengers side near the end of the axle housing tube up near the top facing front to back, another on the drivers side at the top of the diff housing also facing front to back, and one pointing up and down on the drivers side close to the pinion yoke).
another think you can do is get one from a 97-01 explorer, or 01-04 sport track. the diffs are the same, just make sure the gear ratio is the same.
and DO NOT pull the diff, axles and front drive shaft and drive it like that. the axles keep the wheel bearings together, and if you leave it with no axle shafts, your wheels will fly off.

 

[crankyjew]

and DO NOT pull the diff, axles and front drive shaft and drive it like that. the axles keep the wheel bearings together, and if you leave it with no axle shafts, your wheels will fly off.

ohh, DUH. how did I miss that. Good info!

 

[2TimingTom]

Why would your wheels fly off?

The unit bearing is bolted to the knuckle. The knuckle is attached to the upper and lower control arms. The tie rod connects to the knuckle. The brake rotor sits over the top of the lug studs and the brake caliper bolts to the knuckle. Then the wheel is held to the unit bearing via the lug nuts.

Other than the drive shafts, what is different on a RWD Explorer?

 

[vroomzoomboom]

the axle holds the bearing together. the nut puts pressure on one side of the bearing, and the axle shaft puts pressure on the back side of the bearing. thats why you have to torque them to something like 180ft/lbs. there is a difference in 2wd bearings and 4wd/awd bearing. and if you dont want to believe me, pull your axles out of a 4wd/awd and go for a run down the highway