How To: 3rd Gen Rear Pinion Seal and Gear Oil Replacement | Page 2 | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

How To: 3rd Gen Rear Pinion Seal and Gear Oil Replacement

I prefer not to be crawling around under a hot vehicle, personally.

understood, but i am only changing the rear diff fluid... heat isn't a huge issue. I'm wondering if i need the rear diff fluid warmed up for it to properly drain
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





understood, but i am only changing the rear diff fluid... heat isn't a huge issue. I'm wondering if i need the rear diff fluid warmed up for it to properly drain

No, it will drain just fine at room temperature. Be forewarned, it smells horrible no matter what temperature it is.
 






thanks, i got the old fluid out but i am having a ***** of a time getting the new fluid in... it doesn't seem to want to drain in using the gravity feed method. I tip the bottle upside down and it doesnt drain. I've even tried cutting a hole in the top of the bottle which basically just made a mess... i'm out a quart of fluid and on the way to the store to get another one.... any advice so i don't make a mess and waste another quart?
 






Got to squeeze the bottle. You won't get it all out but you only need about 1.5 qts if I remember right so you will have plenty. Don't forget to put in your friction modifier first. Modifier only needed with limited slip diff.
 






i need to replace the front diff pinion seal on my '05 mountaineer. is the procedure the same? the part # i find is different for the pinion seal and i can't find a sleeve listed for the front. is there a sleeve, or does it require one on the front?
 






Thanks, guys. I have been sitting on the write-up for months just because I did not have the several hours to set aside that are needed to get it all posted up and formatted. Hopefully it will help a lot of folks out, even if they just need to know how to take care of the oil in the differential. :cool:

Thank you for your time Josh! I just needed to change mine with 210k on my 06 Exploder!
 






Rear end

Have 2002 Explorer

Interested in getting the rear end under control....

'05 had Ford replace Ring & pinion

'10 Had rear end swapped - with a used one...

* Have replaced the Synthic oil noise improved...

- What about the external rear wheel bearings?

- Is there a good rebuilt unit available - cost?

- Any suggestions on keeping the rear end noise down?
 






Thanks! Excellent write up and pictures. Pics always help a lot. Much appreciated. :thumbsup:
I just did this repair job last Saturday. Went very smooth. Leak is gone now!
 






Is this about the same procedure for the front differential pinion seal as far as the pinion nut and seal installation goes?
 






Thank you. I was concerned I had a leak from the Pinion seal, but after reading your write up and crawling around under my 05 explorer I believe I have a bad gasket at the differential cover. What annoys me is the dealer wanted a service charge just to look and tell me what the problem was.

Chris
 






Thanks for this excellent write up. My wifes 08 Explorer has the same leak and I just noticed it. As luck would have it, we are leaving on Sat for a trip with about a three hour travel time. I'm hoping to have this done by the time we go as I'd hate to have an issue where we run the car for any extended time with low gear oil and just to have it leak out.

Was there any torque specs for the pinion nut?
 






Okay I'm thinking about doing some maintenance possibly this week (change diff oil). Is the front the same...does it follow the same procedure and oil? I've read a few threads and I've read some say that you need to add about a quart more after closing the fill plug. Is this true, could I add the rest through the breather hole?
The front differs mostly in the fact that the cover has a fill plug but no drain, so you simply remove the cover to drain, resealing it with RTV and filling with 80/90 to just below the fill hole. For the rear add an additional 8 ounces through the ABS sensor hole. If working on the floor, level the vehicle as best you can for accuracy, but be safe, rather be a little off on capacity then take a chance.
OP awesome write up, great photos. This helped me, thank you.
 






For the rear add an additional 8 ounces through the ABS sensor hole. If working on the floor, level the vehicle as best you can for accuracy, but be safe, rather be a little off on capacity then take a chance.
OP awesome write up, great photos. This helped me, thank you.

Why over fill it won't that put excess pressure on the seals?
 






That's per the Ford workshop manual. As to why it's done that way, I don't know, but the axle is vented to relieve pressure.
 






That's per the Ford workshop manual. As to why it's done that way, I don't know, but the axle is vented to relieve pressure.

I did not know that.

Thanks for the info. :)
 






couple notes

the flange nut and flange is very tight. 1/2 impact will be a lot easier. when you get the nut off. take a file and cut a small notch in the pinion and on the nut
reason is the paint will come off or get messed up from the sealer.
the nut going back on will go easy till it seats. it will be about 1/4 to 1/8 from where it was. breaker bar will let you go just pasted where the marks are.
if you have on jack stands. can block the tires to keep the pinion from turning.
also the drive shaft don't need to be removed. it will be out of way
The puller is a must DONT try to beat the flange off.
The numbers Josh listed are correct national is 3604
if your can crushes and it will. you can tap rest of way with a light hammer
 






the flange nut and flange is very tight. 1/2 impact will be a lot easier. when you get the nut off. take a file and cut a small notch in the pinion and on the nut
reason is the paint will come off or get messed up from the sealer.
the nut going back on will go easy till it seats. it will be about 1/4 to 1/8 from where it was. breaker bar will let you go just pasted where the marks are.
if you have on jack stands. can block the tires to keep the pinion from turning.
also the drive shaft don't need to be removed. it will be out of way
The puller is a must DONT try to beat the flange off.
The numbers Josh listed are correct national is 3604
if your can crushes and it will. you can tap rest of way with a light hammer

So I new for a few months now that I had a leaky diff and I had cleaned as much of the oily dirt off as I could before and I just crawled under again today and cleaned better. I thought it was the cover seal that was leaking but after reading this how to it definitely is the pinion seal. I'm glad to see because it is a lot less work to do.

So the question I have is if the socket for the flange nut needs to be a deep well or if a regular socket will do?
 






the deepwell works better to hold on to ,but the standard will work.
 






So I new for a few months now that I had a leaky diff and I had cleaned as much of the oily dirt off as I could before and I just crawled under again today and cleaned better. I thought it was the cover seal that was leaking but after reading this how to it definitely is the pinion seal. I'm glad to see because it is a lot less work to do.

So the question I have is if the socket for the flange nut needs to be a deep well or if a regular socket will do?

Don't know how you consider the pinion seal LESS work that just replacing the cover gasket but ok... :thumbsup: It a PITA to remove the pinion nut and the flange sometimes...
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





If it is limited slip diff does it say "limited slip" or is there some sort of code on it?
Bob T
:usa:
 






Back
Top