I have a 9 inch differential, in my 79 Ford F150 4x4. I suspect water being in it. Do I have to pull the whole carrier to drain the fluid?

 

If I remember right yes you have too.And will have to pull the axles to get the carrier out.

 

Ok. Thank you.

 

Is it possible to pull the axle on one side, remove the bolts at the spring ends, and lower that side of the diff.? Will anything fall out, while doing this?

 

Yes, its possible, and no nothing should fall out, but you wont get ALL the old gear oil out. Its really not that difficult to pull both axles and drop out the center section, then you can remove all the old oil. Just be careful when you do pull the center section as its VERY heavy. Some refer to it as a pig....aptly named.

 

This would be a good time to install a locker or limited slip.....

From memory:

1. Place truck on jack stands.
2. Remove both rear wheels
3. Release the parking brake
4. Remove brake drums
5. Mark the driveshaft and the pinion so it can be reassembled in the same phase.
6. Disconnect the driveshaft at the pinion and swing it out of the way.. suspend it using wire or rest it on a milk crate.
7. Through the axle flange, remove the four nuts securing the axle retaining plate.
8. Pull each axle out about 8 to 10 inches. You will hear a telltale "clunk" when it is freed from the rear gear assembly.
9. At the third member, use a 3/8" or 1/2" ratchet extension to loosen the fill plug. It's easier to confirm it can be loosened now that when it is reassembled.
10. Remove all but one nut at the top of the gear carrier. Loosen the top nut but leave it slightly threaded.
11. Place a drain pan under the rear gear and pry the gear carrier away along the bottom.
12. Let 'er drain.
13. With some sort of low platform (like another milk crate), remove the last nut and place the gear assembly on the platform... WATCH OUT.. that ***** is heavy!!
14. Use lots of rags to remove the remaining gear oil. Check for metal shavings while you're at it. Use brake cleaner as a surfactant if ya have to.
15. Clean the gear carrier's mating surface and the axle housing's mating surface. Remove all traces of old gasket material and/or RTV.

Installation is the reverse of removal. Please use a torque wrench.

Going it at it alone should take about an hour... no, really... one hour!!!

Notes:

• Apply RTV around all the studs on the axle housing when reinstalling the gear carrier. This is very important if using a gasket because you need to do it on both sides of the gasket.
• A little RTV goes a long way. It it oozes out then ya used too much. About a 1/8-inch wide bead is all it needs.
• Wait about two hours before refilling the rear axle with lube to give the RTV some time to set up.
• Refill the axle lube until it starts to drip out of the fill hole.

 

Thanks HIO. A local mechanic suggested, drilling a hole, tapping it and adding a drain plug. What do you think about that? Also, first of all I put new bearings and seals on both rear axles. The bearing race on the left side, I was able to turn it a little with my hand, after it was installed in the housing. He also suggested pulling the race back out, clean the housing with break cleaner, and putting some loctite on the race, which I have already done. What do you think about that? If I decide to pull the center section, with the loctite being on there for about 3 or 4 days now, will the axle come out without damaging the new seal? Also, there is fluid leaking from the pinion. Not from around the pinion flange, where you see most leaks from the seal, but, through the pinion shaft, behind the nut. Right there where you bolt the driveshaft to the pinion. The mechanic, was going to remove the nut, and put some kind of sealer on the shaft. He said it was a special sealer made for that, that would never seize up on the shaft. Do you know of this substance, and what it is called? How hard is it actually to pull the pinion, and install a new seal? Is there some kind of bearing preload procedure, or can I simply re-install the pinion and torque it? I printed a manual on the Dana 44 that Redroad had sent me a link to, but, I'm not sure if the Dana 44, and the 9 inch, are one and the same.

 

You're welcome.

No need to drill and tap. Replace one of the lowest studs with a bolt. It'll drain slower but it'll drain nonetheless.

That's OK to do. I apply Loc-tite on engine core plugs AKA "freeze plugs". Same principle.

It should be fine if ya pop it out evenly.

I don't know of the sealer. Personally, I wouldn't do what he is suggesting. I would bring it to the shop and have it done... Like I stated previously, it would be a good time to install an LS or locker.

If you have to ask then it is beyond your capabilities because it has a crush sleeve plus you'll need specialized tools to reset the tooth pattern, pinion depth, and preload. I leave that to the pros.

The Ford Nine and the Spicer-Dana 44 are totally different animals. Trust me, have the pros rebuild the center section (pig, gear carrier, third member).

 

Thats good to know, about draining the fluid out of the lower bolt hole. Every vehicle has their own little secrets. You just have to learn them as you go along, and you just saved me a lot of money, by filling me in on that. Thank you, again. I just never have worked on any Fords, before I took on this project truck. I've always been partial to Dodge. I don't know why, after seeing how easy most everything has been to work on, on this truck. I am a mechanic by trade. I have an Associates Degree in Auto Mechanics. And, I worked for Chrysler for about 10 years, plus I was a Mechanic in the military. I've rebuilt engines, transmissions, transfer cases...I just haven't had a differential on the operating table, yet. Yesterday, was the first time I ever removed a carrier from a front differential, and replaced the inner axle seals. The book showed a special tool to remove and install the seals, which I did not have, and could not find locally, or on Ebay. I improvised, and invented an installation tool. I just put a piece of 1/2 inch galvanized pipe through the end of the axle tube, and the seals tapped out, real easy. The installation is where the invention came in. I ran a piece of 1/2 inch all-thread through a 1 inch board (against the end of the axle tube, not the steering knuckle. That way I was working on the most square surface with the inner seal), through the axle tube, through the seal, and through a 1 3/4 inch, 3/4 inch drive, socket (which fit perfectly into the cup of the seal). Put a nut and a washer on each end, and tightened it up, from the inside, so I could see that the seal was going in straight. Those seals slid in just as slick as whistles. I think I need to get a patent on my new invention.