So I look under my truck today and the front pinion shaft seal is leaking. There is little oil on the underside of the truck so it must have just started today. So how do I replace this thing? It looks like a pain in the ***.. any help is great!

 

you take it to a shop.

my seal was leaking, so i got it fixed and now it is leaking again.
they said the seal is fine, but the part the seal sits on has about a ten thousands grove in it...thats why it is leaking now.

you have to drop the front drive shaft to replace it.
someone did it on the site and said it was very hard.
search for it, there has been a lot of talk about the front diff. leaking lately.

 

its very easy if you have air tools .... ive replaced alot of them ... mostly rangers/explorers fronts, and 250s 350s rear seals ....

ford actually now has an updated front seal for the rangers/explorers ...

 

I'm pretty sure I 'can' do it.. but dont know how.. can you elaborate on what needs to be done exactly?

 

Well i did both axle seals and the pinion seal on mine and it was a royal PAIN in the @$$....IT sucked...i have air tools and it didnt make it any easier because you have to find something to knock it into place evenly, you cant hit one sit in and then the other, or it will just keep popping out...Im not even sure if mine stopped leaking yet or not, i have to wait and see if it comes out, its been a couple weeks...if it leaks again im taking it to ford....Basically what i did for the pinion is remove the driveshaft, take a screwdriver and pry the old one off...took awhile and cleaned all the old silicone off, should be orange...and put new silicone on the new one, even though it comes with some from ford...and couldnt find anything to put it back in with, and finally found something....a CAP to a fence post, works perfect...after some fighting i got it in and evened up, and put the axle back in....i hope it doesnt leak because its a PITA.....Also putting new front diff fluid in is hard


Rocky

 

i ran mine leaking for a few months. prolly 6k+ when they pumped the oil out he said he pumped over or right around 2 quarts which is what the front diff requires. i got mine done for $35(front pinion) and $65(back pinion). its not leaking now which im happy but since i found out hardly any was lost while it was leaking i wish i wouldnt have even spent the money to have it done.

there is another thread on here where someone said how to do it. and what special tools are required.


here are the instructions for a f150 so it should be simular



> > Drive Pinion Seal
> >
> >
> > Special Service Tool(s)
> >
> >
> > 2-Jaw Puller
> > 205-D072 (D97L-4221-A) or Equivalent
> >
> >
> > Companion Flange Holding Tool
> > 205-126 (T78P-4851-A)
> >
> >
> > Converter Oil Seal Remover
> > 307-309 (T94P-77001-BH)
> >
> >
> > Pinion Seal Replacer
> > 205-133 (T79P-4676-A)
> >
> >
> > Removal
> >
> > CAUTION:
> > This operation disturbs the differential pinion
> > bearing preload. Carefully reset the preload during
> > assembly.
> >
> > 1. WARNING:
> >
> > Raise and support the vehicle. For additional
> > information, refer to «Section 100-02».
> >
> > µ 2. Index-mark the front driveshaft and pinion
> > flange.
> >
> > µ 3. CAUTION:
> > Do not allow the driveshaft to hang unsupported.
> >
> > Disconnect the front driveshaft from the pinion
> > flange, and position it aside.
> >
> > 1 Remove the bolts and the universal joint spider
> > retainers.
> >
> > 2 Disconnect the front driveshaft from the pinion
> > flange.
> >
> > 3 Position the front driveshaft aside.
> >
> > µ 4. Measure the pinion bearing preload.
> >
> > l Using a Nm (inch-pound) torque wrench, measure
> > the torque required to maintain pinion rotation.
> > Record the measurement.
> >
> > µ 5. Index-mark the pinion flange and the pinion
> > stem.
> >
> > µ 6. Use the special tool to hold the pinion flange
> > while removing the nut.
> >
> > µ 7. CAUTION:
> > Place a drain pan under the differential housing.
> >
> > Using the special tool, remove the pinion flange.
> >
> > 8. Inspect the pinion flange for burrs and damage.
> > Inspect the end of the pinion flange that contacts
> > the bearing cone, the nut counterbore, and the seal
> > surface for nicks. Discard the pinion flange as
> > necessary.
> >
> > µ 9. Using the special tool and a suitable impact
> > slide hammer, remove the pinion seal.
> >
> > µ 10. Remove the front axle drive pinion shaft oil
> > slinger and the differential pinion bearing.
> >
> > 11. Remove and discard the collapsible spacer.
> >
> >
> > Installation
> >
> > 1. Verify that the splines on the pinion stem are
> > free of burrs. If burrs are evident, remove them
> > with a fine crocus cloth. Work in a rotating motion
> > to wipe the pinion clean.
> >
> > 2. Clean the pinion seal bore.
> >
> > 3. Install a new collapsible spacer.
> >
> > µ 4. Install the original differential pinion
> > bearing and the front axle drive pinion shaft oil
> > slinger.
> >
> > 5. Lubricate the pinion seal.
> >
> > l Use Motorcraft SAE 80W90 Thermally Stable 4x4
> > Axle Lubricant meeting Ford specification
> > WSP-M2C197-A.
> >
> > µ 6. Using the special tool, install the pinion
> > seal.
> >
> > 7. Lubricate the pinion flange splines.
> >
> > l Use Motorcraft SAE 80W90 Thermally Stable 4x4
> > Axle Lubricant meeting Ford specification
> > WSP-M2C197-A.
> >
> > µ 8. CAUTION:
> > Never use a metal hammer on the pinion flange or
> > install the flange with power tools. If necessary,
> > use a plastic hammer to tap on a tight fitting
> > flange.
> >
> > Align the index marks and install the pinion
> > flange.
> >
> > µ 9. Install the new nut hand-tight.
> >
> > µ 10. CAUTION:
> > Do not loosen the nut to reduce preload. Install a
> > new collapsible spacer and nut if preload reduction
> > is necessary.
> >
> > Use the special tool to hold the pinion flange
> > while tightening the nut to set the preload.
> >
> > l Tighten the nut, rotating the pinion occasionally
> > to ensure the differential pinion bearings are
> > seating correctly. Take frequent differential pinion
> > bearing preload readings by rotating the pinion with
> > a Nm (inch-pound) torque wrench. The final reading
> > must be 0.56 Nm (5 lb-in) more than the initial
> > reading taken during removal.
> >
> > µ 11. Align the index marks and position the front
> > driveshaft.
> >
> > µ 12. Install the universal joint spider retainers
> > and bolts.
> >
> > 13. Check the fluid level and, if necessary, fill
> > the axle to specification.
> >
> > l Use Motorcraft SAE 80W90 Thermally Stable 4x4
> > Axle Lubricant meeting Ford specification
> > WSP-M2C197-A.
> >
> > 14. Lower the vehicle.
> >
> > 15. If so equipped, reactivate the air suspension.

 

Well ...

you need to removed the front driveshaft from the front diff when doing so mark where the driveshaft is at on the flange. the bolts for the front drive shaft are a torx bit ... a T30 ( you can leave the front drive shaft attached to the tcase )

once that is out of the way mark where the ...
NUT
FLANGE
are located on the pinion shaft

now you can remove the nut from the pinion

once you do that, use a puller to pull the flange off the pinion

once that is done you can remove the seal, either a seal remover, or you can just get a flat head screw driver and tap it around the edge to get under it and 'pop' it out/off the diff.

with the new seal there is a spring on it, be very carfull not to damage the spring when installing the new seal. if you do it will leak. i use somethign called "Trans Gel" it will hold the spring in place in the seal and help reduce the risk of damaging it when u install it. it is like vasaline ...

when u go to install the new seal get something that is the same size as the seal surface to beat on so it installs it evenly.

once the new seal is in you can install the flage ( using the mark you made before hand line it all up )

then install the nut, tighten it up untill it starts to get to be 'tight'

once it is tighten it up to the mark you made before hand ... and then a little further than that. while tightening it spin the pinion gear to make sure it did not bind up.

once it is good, reinstall ur drive shaft with the mark you made before.

clean up ur mess, check ur fluid level add if needed and you are good to go.


i hope that helped ... any questions just ask away.

-jared

 

Hmm... Just finished doing all the seals and bearing in my rear and about to do the same for the front tomorrow. I also happen to be doing my front hub assemblies so I am looking at dropping the whole front diff. Looks to be the easiest way considering there's only really three mounts holding it in once you've pulled the axles. Almost looks too straight forward, has anyone else gone with this approach?