Leaking Rear diff? (1 Viewer)

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I just got back from a long trip and I am slinging soem sort of lubricant from the rear of the truck. My tranny fluid is the same as the beginning and so is the oil. Plus there is not much mess in front of the rear diff.
So I am thinking the rear differential. Is this a common leak and what do i need to fix it? Do the gaskets go out on these things much?
I need to fix this leak soon, there is a lot of juice falling out.

Thanks
Kent
 
livelarg said:
I just got back from a long trip and I am slinging soem sort of lubricant from the rear of the truck. My tranny fluid is the same as the beginning and so is the oil. Plus there is not much mess in front of the rear diff.
So I am thinking the rear differential. Is this a common leak and what do i need to fix it? Do the gaskets go out on these things much?
I need to fix this leak soon, there is a lot of juice falling out.

Thanks
Kent


Kent, can you give a little more info on you Cruiser. Year model, mileage, etc..

I am not aware of any real problems with dff. gaskets (3rd member to housing) but pinion seals can leak and cause a mess. A photo would be handy, or you could thoroughly clean the area and then look again in a day or so to see if you narrow it down.
 
Sorry, I guese that whould be helpfull.
It is 91' cruiser with 220K miles on it. I just bought it about 2 months ago. The guy that owned it before me did not take the best care of it.
I did clean it off once, and it did not seem to be leaking, but on this last drive, it seems to be slinging fluid all over the area around the rear diff.
My current plan is to clean it off again then drive for a few miles to see where it is leaking from.

Thanks
Kent
 
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I too would look at the seal for the pinnion. Mine was leaking there and would run down the pumpkin and drip on my driveway. Cheap fix if that is the cause.
 
Kent, what makes me think it is a pinion seal is the fact that lube is being thrown all about. This suggests a leak at a rotating part (namely the pinion gear/shaft), and then the yoke is slinging it all over.

If it were a gasket at the third member you wouldn't see the kind of mess you're describing. It would be "wind blown" around the housing but thats about it.

Good luck.
 
Cool, thanks for the info.
I am not sure what you are meaning with the pinion seal. you say it is a cheap fix, any where I can find info on how to do it?

Thanks
Kent
 
livelarg said:
Cool, thanks for the info.
I am not sure what you are meaning with the pinion seal. you say it is a cheap fix, any where I can find info on how to do it?

Thanks
Kent


I didn't say it was a cheap fix (although it can be). The seal itself is inexpensive.. but if you have to pay someone to do the job it could run into a litte money.

The seal resides behind the companion flange and underneath a dust cover. It can be removed on the vehicle but care must be taken when retorquing the flange nut so as NOT to change the pinion preload.

Also, its possible that the pinion shaft has a groove in it. This can happen when a seal starts to fail and dirt/dust etc....get into that area and wear a small groove in the sealing surface.

Eventually, even a new seal will leak again if this isn't taken care of... (redi-sleeve).

So....the gist of is: You can buy a seal and do it yourself (after having read how in the FSM) or, you can pay a shop to fix it.

One stumbling block might be the torque figure on the companion nut. I don't have my manual in front of me...but I'll bet its way on up there. (anybody know)
 
thanks, but what is the FSM?
 
I replaced my rear pinnion seal a few months ago. The part was less than $7 at Advanced Auto. I used a friends lift and it was quite easy.

FSM=Factory Service Manual
 
flintknapper said:
One stumbling block might be the torque figure on the companion nut. I don't have my manual in front of me...but I'll bet its way on up there. (anybody know)
IIRC the final torque was 180#
So you need access to a footpound torque wrench that goes at least to 180#
as well as an inch pound torque wrench to determin preload before you remove the pinnion nut.
There is alot of info I found when I fixed mine, try searching for Pinnion, Companion flange, leaking pinion, You should be able to find some good info.

If the oil is coming out at the end of the pinnion from under the nut, or is comming out from between your companion flange and the pinnion housing then you might look at you companion flange seal a little closer.
 
Thanks for all of the info, I am about to get on this thing tomarrow.

Thanks
Kent
 
If you have not done this before, it would be a wise choice to have help. you can put too much preload on the bearing and it can fail(if it has not already). Typically the 180# is for the new install on new bearing with a new crush sleeve. That is why you need the second inch # torque wrench. to measure the bearing preload. If the bearing is not too loose you usually can tighten the nut a little past the old stake point on the nut, if the bearing moves smoothly and does not bind. Try to adjust bearing preload with the axles in the houseing is somewhat difficult to get right, that is why I say it might be good to have help form some one that can help you. Or find a good toyota truck/crusier shop to do. Should be about what ever the minumum labor rate a shop has or no more than a 1 time and the seal cost with maybe a fluid drain and fill if it has not been done in a while. good luck robbie
 
Anyone know of a link to somewhere that has a step by step instructions.

Now to end with a dumb question...
What kind of fluid do I refill with, and where does it go?

Thanks
Kent
 
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livelarg said:
Anyone know of a link to somewhere that has a step by step instructions.

Now to end with a dumb question...
What kind of fluid do I refill with, and where does it go?

Thanks
Kent

You refill it with gear oil. Check owners manual for type. 80/90 or 75/90 if I remember correctly. There are lots of opinions as to type of gear oil. Do a search on here (including the FAQ up top) for more info.

There is a drain and a fill plug on the back of the pumpkin. Drain is on the bottom (facing the ground) and fill is up near the top. It's critical that you remove the fill plug first. They can sieze in place, and you don't want to find that out after you've drained the oil out!
 
I did a search onb the pinnion and compantion flanges, didn't get more usefull info on how to do it tho'
I really need to get the FSM.

Thanks
 
livelarg said:
I really need to get the FSM.

Thanks

Yes, you do. Although, I've found in some diagrams, it's inaccurate as it shows older parts from the FJ62, since they have the same engine and trans. Don't believe me 91 owners? check the brake fluid resevoir diagram.
But still... the FSM is invaluable and a must have if you intend on even changing your differential fluid.

Now... per your signature, how did you "body" lift you truck?
 
Land Speeder said:
Now... per your signature, how did you "body" lift you truck?

The body lift was done before I got it. It was done using aluminum pucks for the lift. It looks like it is a professional kit. The guy did a good job tho' Everything works perfect and it rides like stock.

Here are a couple of pics of the truck and the lift. Had to throw in a pic of both my rides
:D

The cruiser is running 32x11.5
DSC00243.jpg
DSC00245.jpg
DSC00244.jpg
 
Land Speeder said:
Dude, we got the same colored and year truck...
I wonder if they came off the line close to each other...



Cool! I hope you like yours as much as we like ours! :D
 
Back on the rear diff leak thought...

I just got back in from looking at my '94 80's rear diff (sans lockers). It's got a gentle leak out the front, which makes me believe it might be the pinion seal. It also seems to make a bit of (quiet) whine on the freeway. Any thoughts on the sound?

(Apologies for the semi-hijack)

-Brandt
 
I need to replace my front dif pinion seal now as it is now puking dif oil... I guess my 91 is feeling sympathetic for the look'a'like

The FSM has, count'em, 6 SST just to get down to the outer race and then all back on!
So what is truly needed to replace the seal only if I stop there?
What would suffice for a companion flange puller? And then what removes the seal? Both of those steps have crazy looking SST's, and I ain't gott'em.
 

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