My front differential is leaking from all possible locations (pinion and both axles). I want to go in and replace the seals but was wondering if anyone has a diagram from a service manual that they could share to help me out. I have the haynes but it is pretty much useless.

Also if you have any aditional tips they would be greatly appreciated. If it's not too much additional work I will be replacing bearings and seals at the hubs.

I did the rear a couple months ago and it was a breeze, but I am reluctant to be that optimistic about the front diff. Thanks.

 

Well the front diff needs to come out for you to work on it, maybe getting a used one is a better choice?

 

i also need a diagram.... actually a parts break down so i can be sure to get all the correct parts.

 

http://www.therangerstation.com/tech...ams/99D35X.jpg

 

Thanks for the diagram.

Maybe I didn't explain my situation well. There is nothing wrong with the diff. with the exception that the seals are leaking. The seals are $20 while I would imagine buying a new differential would be a much greater expense and require the same amount of labor.

I plan on replacing one of the half shafts as well (opportune time) and the seal I am talking about is the one between the half shaft and the diff. How difficult is it to get that in and out of there? I would imagine there is also a bearing there as well so do you have to drop the diff to change out the bearing and seal?

The pinion seal is pretty much the same as the rear end so I am not concerned about that. Just the other two seals/bearing where the half shafts connect. Thanks again for the diagram, it may come in handy.

 

If no one else pops up with help I will take some pictures when I do mine starting next monday and post them here.

 

It will be easier to pull the diff out to change the seals, as the space is limited with it in the truck. Hence getting a used unit for 100 or so.


While you are at it I would check the wheel bearings as this will be the best time change them. Add ball joints to the list.

 

Does it take any special tools to separate the half shafts from the diff or is it pretty much just a pickle fork?

 

They just pull off with a tug.

 

thanks for posting that link to the diagram, i already found that one but i cant find any part numbers. most parts stores in my area cant/wont get me a full rebuild kit or cant/dont know how to piece together everything i need.

 

NAPA seal parts numbers for the front axle...

Left side: 13757 SKF
Right side: 17520 SKF

There is also a needle bearing on the long side for hte inner shaft, but should not need replacing unless you have issues with it.

Have yet to do a pinion seal for the front, but it does use a crush sleeve if I'm not mistaken. Not sure if you like to do the "real" way to do seals on axles with crush sleeves, or the "calibrated hand/paint/whatever" method....in any case, any decent parts house should have no problem getting the pinion seal and crush sleeve.

Tips: Drop the whole axle, it's not hard at all. You really don't even need to take apart the pass side knuckle if you remove the drivers side. You can't really get at that seat to install, save yourself the headache and just do it all on the bench after removal!

 

started the preliminary settup today and yeah it looks like taking the diff out completely is going to be not that bad. I am likely going to replace the passenger side half shaft so it comes part...no biggie once I get past the rust. What size is the retaining nut on for the half shaft? I have to pick up the tools in the morning. Everything is soaking now with WD40.

 

I find this interesting since O'Reilly gave me two of the same seal and said it's the same on both sides.

 

WD40 is just mineral oil and a solvent really worthless stuff.

The axle nut is 32mm IIRC. Ford wants them replaced if removed, so the new half shaft should come with one. Use it to get the the right socket.

 

Plan a trip to return at least one, they are not the same. One is larger than the other, pass side IIRC

After looking at my spare front axle, there is also a bearing on the short side, but again, should not need replacing unless giving you trouble.

 

Orielly gave me two pinion seals and when I returned them I had to explain the difference...then I drove 2 blocks to NAPA and had the correct seals in seconds.

Anyway, the diff was pretty easy to drop and seals pretty straight forward. One new halfshaft installed. Now I am stuck on the pinion nut...I hate those things...if I can't break it free in the morning I will be trying to locate an impact wrench for rent. 3' breaker bar and no love...soaking over night, try heat in the morning...then off to locate an impact wrench.

 

Use an impact, much easier. Even if you need to put it in the trunk and take to an auto shop.

As far as the wrong parts, the computer only gives you the right numbers if you know how to work it and know what your looking up. Oreilly's carries the parts, they are called axle shaft seals.

http://www.oreillyauto.com/site/c/se...1999&make=Ford

 

You are correct, but the Orielly I was at wouldn't even allow me to view the monitor to see what she was doing let alone run the computer. I had the NAPA parts numbers written down as I looked them up from home but I had to return the old ones to Orielly and thought i would give them a second chance. No big deal, but I do expect the clerk at the parts store to know what the pinion is vs the axle and she had no clue...

Impact wrench is the plan, have to see if I can rent one today from Hertz.

 

What an uppity control freak, every parts counter I have ever been too they let me look at the screen if I had questions. Or if they were unsure. You were absolutely right in taking your business elsewhere. I just hate running for around town for parts .

I think we all know not to trust any of them.