Rear Axle Seal (2 Viewers)

[ColoradoFJ40]

Is it possible to change thie both rear axle seals without removing the diff and c clips? I have a FSM but it is not here or I wouldn't be asking. I'm pretty much a noob and this will be my first time tearing into the rear. My rear doesn't leak so I am trying to avoid opening it up.

Thanks for the help.
Mark

 

[Josie'sLandCruiser]

Hi All:

You don't have to remove the rear third member, but the rear axle shafts will need to be removed to replace the rear axle seals.

Drain the rear diff, remove the diff cover, remove the "C" clips, then pull-out the rear axle shafts. Remove old seals, install new seals, insert axle shafts, insert "C" clips, install & seal diff cover, re-fill with gear oil, then bolt on wheels/tires.

Good luck!

Alan

 

[Poser]

My rear doesn't leak so I am trying to avoid opening it up.

Why are we changing seals?

 

[ColoradoFJ40]

Why are we changing seals?

Well, I have the body off the frame and I am about to sand blast, paint and put new suspension on. So painting the axles is on the list but thought as long as I am at it why not do it to avoid something later. PS. I need to order some rear rotors from you.

Should I leave them alone?

 

[antFJ]

if they dont leak then why mess with them!

is this a truck that has been recently been running and driven? if so they you should be able to tell if they need to be replaced.. if this is a truck that has sat for a while and you're doing a complete tear down then i'd say replace them

 

[ColoradoFJ40]

if they dont leak then why mess with them!

is this a truck that has been recently been running and driven? if so they you should be able to tell if they need to be replaced.. if this is a truck that has sat for a while and you're doing a complete tear down then i'd say replace them

It sat for a good 10 years for the most part. I was told it was driven on and off every 3 or 4 years around the farm. Before I tore it down I drove it about 5 or 6 miles. It doesn't appear to have any leaks, but it's sat a long time and I am doing a complete tear down.

 

[BlueCruiser84]

Yes, take the rear cover off the diff, but leave the third alone. Pull the carrier cross shaft and c-clips and slide the shafts out.

If it sat for that long and you will be tearing into the rear axle I would change them... and possibly the bearings if you are already in there. However, they are just as easy to change with the body and everything else in place.

Brian

 

[jmdaniel]

Resurrecting this thread...

I am going to replace my seals, (one is bad, I'll replace both while I have it apart), and I'm a bit confused after reading threads here, and comparing them with the Haynes and FSM. Haynes mentions pulling the c clips and shafts, but also states that the pinion shaft pin, pinion shaft, and shaft spacer has to come out before the c clips are pulled. The FSM states the same as the Haynes, and then goes on to state that the differential gear backlash needs to be measured when putting everything back together, and if outside the standard value, a gear thrust washer must be used.

Most of the stuff I've read here doesn't mention the pinion stuff needing to be pulled out, so for those that have done this, is it necessary? And if it is, is the backlash measurement/adjustment needed? This is the first time I'll be opening up the diff, so I wanted to know everything I could before I got started. Thanks for any help!

 

[bikersmurf]

It is not necessary to mess with the Pinion. There is a block between the ends of the axle shafts which needs to come out to allow the c clips to be removed. The suggestion in the FSM is to check clearances while your in there is to prevent any surprises down the road.

You may find piting on your axle bearing surfaces when you get in there... don't ask me how I know...




1974 FJ40 w/ FF front and REAR...

 

[Poser]

Haynes mentions pulling the c clips and shafts, but also states that the pinion shaft pin, pinion shaft, and shaft spacer has to come out before the c clips are pulled.

The pinion shaft that they are referencing when talking about removal of the c-clip rear axle shafts is the spider gear pinion shaft; the shaft that the spider gears rotate on. This is retained into the carrier by the pinion shaft retaining pin that typically has a 12mm head and threads into the carrier through the pinion shaft. After this pinion shaft is removed, the thrust block, spider gears and spider gear thrust washers can be removed. The axle shafts can then be tapped inward, the c-clips removed and the axle shafts removed from the axle housing.

 

[jmdaniel]

But Poser, my question is does all that need to come out?

 

[Bret]

Don't confuse the pinion reference to the pinion that is attached to the driveshaft flange. The pinion and carrier stay in place. Once you pull the cover off if you are using anything other than a 12mm wrench you are taking off the wrong part.

Pull the cover and look through the hole in the carrier. It is the main piece you will see with the ring gear bolted to it. With the large opening facing you you should see the side gears that are splined on the inside for your rear axles to slide into, two small gears (spiders) that are riding on the cross shaft (there are shims under those gears so keep track when you remove them), and a block that is also on the cross shaft in the middle between the spider gears (this keeps the axle from being pushed in and allowing the c-clips to fall off). If you look on both ends of where the cross shaft comes through the carrier one end will have the bolt Poser is referring to. Once you remove that bolt it should allow the cross shaft to slide out. It may only come out one way so you may have to rotate the carrier a little to make room for it to come out. As it slides out be sure to watch for the shims behind the spider gears and the block that will fall out. Once that is out go to the side of the rig and give the axle a little push towards the diff and that should release the c-clip. You may have to push the side gear back into the carrier if it moved in with the axle. Once the c-clip is off you can carefully slide the axle out. This is easier without the tire on depending on tire size.

If the cross shaft does not just slide out it may have gotten damaged and can be a bear to get out.

If your careful you can probably do it without the spiders coming out but the shims always fall out when I take the cross shaft out.

 

[jmdaniel]

Well, these answers display a wide range of things that need to be done, from drain diff/pull cover/pull c clips/pull shafts, to much more than that. I can match most of what's been said to the FSM, except for Bret's mention of the spider gears and shims coming out. Why would that not be in the FSM?

 

[LAMBCRUSHER]

Well, these answers display a wide range of things that need to be done, from drain diff/pull cover/pull c clips/pull shafts, to much more than that. I can match most of what's been said to the FSM, except for Bret's mention of the spider gears and shims coming out. Why would that not be in the FSM?

between what has been posted by both Bret and Poser, you have the how to's. it will make more sense once you dig into it. keep mud on line and some rags near the keyboard so you can ref the tech when you need to-or get FSM. it is not that hard, just make sure everything gets back to where it needs to go to run it(shims behind spider gears) It is almost eggzackly as yo state in what I quoted, the extra bits I think you are referring to are just details of the pinion cross shaft removal/install. there are gears which ride on the shaft that has to be removed for you to push the axles into the housing enough to get the c clips off to get the axles out. there are thrust washers behind those gears. as you rotate the carrier to gain access to the pinion shaft and inside stuss, there is HIGH likelyhood that the thrust washer(s) will slip out from behind their spider gears. You need to make sure those get back to where they belong. it really isn't "much more than that" as you are concerned that it may be. if you are confused by what you encounter as you tear into it, then refer back to mud. if I can do it.........

 

[Poser]

But Poser, my question is does all that need to come out?

The pinion shaft that they are referencing when talking about removal of the c-clip rear axle shafts is the spider gear pinion shaft; the shaft that the spider gears rotate on.


This is retained into the carrier by the pinion shaft retaining pin that typically has a 12mm head and threads into the carrier through the pinion shaft.


After this pinion shaft is removed, the thrust block, spider gears and spider gear thrust washers can be removed. The axle shafts can then be tapped inward, the c-clips removed and the axle shafts removed from the axle housing.

Slow down and read what has been presented.


Do not read into anything.


When you have these pieces in front of you and your hands dirty, this will all come together for you.

 

[hellbent40]

jmdaniel if your part of a local club there in texas i am sure that someone in that club has torn one of them apart more than once..

maybe get someone to show you how the first time and its easy after that...

 

[jmdaniel]

Thanks, guys. I'll quit being such a whiny little bi*ch and dig into it.

 

[tucker74]

It's not that big of deal - rotate carrier, remove bolt, pull pin, remove spacer & spider gears (note placement for re-assembly), push in axle(s), remove c-clip, then you can pull axles to get to seals. You don't need to remove the side gears, but hold them in place with one hand when you re-insert the axle (note orientation if you do remove). If you put it all back the same then no need to measure backlash, but its a good time to if you want to check for wear

Had mine apart last week to install a locker -

Tucker

 

[jmdaniel]

All right, did these today. Not too bad, with the worst part getting the spider gears back in and lined up. Thanks, guys!