how hard is this TC leak to re-seal

[BostonJon]

hi everyone -

Was replacing my rear shocks and coils over the holiday break and noticed that my transfer case was wet at the bottom. from what I can tell, the seepage is coming from where the 'case cover' is bolted to the 'front case'. this seems to be originally sealed with red FIPG. i dont think the leak is coming from the oil seal that is pressed into the 'case cover' but i'm not 100% sure. see attachment for part names.

questions for the collective wisdom here:

1) is it possible to reseal the 'case cover' and/or replace its oil seal while the TC is still mounted to the truck?
2) if I wanted to reseal the whole thing, seems like mbtim has a video for removing the TC entirely and it doesnt seem all that bad.
3) the truck has 401k on it and this is the original TC. if im going to go through the trouble of taking it off the truck, would it be wise to swap it out with a lower mileage unit

 

[brillo_76]

I personally just drop the transfer to work on it any besides gear grease checks or changes. Just to give me more room to work on it.

Up to you if you want to replace it with a loe milage one. If you go that route, you can just reseal the low mileage one then swap it in.

I haven't seen alot of transfer cases fail. How does the fluid look in your transfer case? Alot of material in it? Or is it super clean?

Sent from my SM-J337V using Tapatalk

 

[Bad Luck]

hi everyone -

Was replacing my rear shocks and coils over the holiday break and noticed that my transfer case was wet at the bottom. from what I can tell, the seepage is coming from where the 'case cover' is bolted to the 'front case'. this seems to be originally sealed with red FIPG. i dont think the leak is coming from the oil seal that is pressed into the 'case cover' but i'm not 100% sure. see attachment for part names.

questions for the collective wisdom here:

1) is it possible to reseal the 'case cover' and/or replace its oil seal while the TC is still mounted to the truck?
2) if I wanted to reseal the whole thing, seems like mbtim has a video for removing the TC entirely and it doesnt seem all that bad.
3) the truck has 401k on it and this is the original TC. if im going to go through the trouble of taking it off the truck, would it be wise to swap it out with a lower mileage unit

1) The case cover is between the transfer case and transmission so you would need to remove it if that's where you think your leak is.
2) I haven't done it, but it's typically not that bad.
3) If it's not making any noise and the fluid looks good then I wouldn't swap it.

 

[calimobber]

Yeah I think it would be pointless to try and do still under the car. The transfer case isnt too bad to remote and reinstall ive done it before using a transsmistion jack.


Unless its leaking bad I wouldnt bother even fixing unless its actively dripping. old cars leak a little and a little oil looks like allot more than it really is. Just dont look at it haha.

 

[BostonJon]

thanks, everyone. the fluid is clean (i just drained/filled about 6 months ago) and the shifts into and out of 4wd are very smooth with no hesitation, grinding, etc.

This is far from a scientific measurement, but it leaks at the rate of about one drop on the garage floor every week or so.

 

[brillo_76]

That's an extremely slow leak. At that mileage that's great..

Sent from my SM-J337V using Tapatalk

 

[BostonJon]

That's an extremely slow leak. At that mileage that's great..

Sent from my SM-J337V using Tapatalk

but a leak is still a leak...

 

[Devbot]

but a leak is still a leak...

And with gear oil it has to be fairly substantial to make it through.
Regardless, he's just flipping shit. Of course you should address a leak instead of going "ahhh, shes just old"

 

[FD7683]

If addressing the leak requires the whole assembly to come down and also wondering on how to do it, I would just leave it alone if the leak is very small. I know some people (like me) that are OCD with their maintenance

"if it ain't broke, don't fix it." I do ignore this a lot so it's ok.

 

[gamefreakgc]

Mine leaks in the same location, except I don't have any drips yet. It just stays wet. Fluid levels haven't dropped anything significant over 6 years of ownership so I never bother to fix it.

Our rigs leak as they age but not nearly as bad as other cars. It just comes with the territory of owning a very high mileage vehicle.

 

[Bad Luck]

I wouldn't fix a leak that small if it means having to remove the transfer case, but to each their own

 

[BostonJon]

update here -

i cleaned the TC again to see if i could get a better indication of where the leak was coming from. after checking again, it appears that the top of the TC is actually wet with fluid and this fluid is seeping down the TC housing.

I remember reading some threads about people replacing a seal at the top of the TC where the 4WD shifter comes up through the transmission tunnel. this appears to be done from the interior of the vehicle. Of course, now I cant find that thread despite searching.

Would it be possible that my leak is coming from that seal at the top of the TC?

 

[Bad Luck]

update here -

i cleaned the TC again to see if i could get a better indication of where the leak was coming from. after checking again, it appears that the top of the TC is actually wet with fluid and this fluid is seeping down the TC housing.

I remember reading some threads about people replacing a seal at the top of the TC where the 4WD shifter comes up through the transmission tunnel. this appears to be done from the interior of the vehicle. Of course, now I cant find that thread despite searching.

Would it be possible that my leak is coming from that seal at the top of the TC?

That's a fairly common area for the transfer case to leak at. It's done through the body on top. I think this is the procedure you're looking for: DIY/ How to Change 3rd Gen T4R Transfer Case Shifter Gasket

 

[BostonJon]

That's a fairly common area for the transfer case to leak at. It's done through the body on top. I think this is the procedure you're looking for: DIY/ How to Change 3rd Gen T4R Transfer Case Shifter Gasket

yes! thank you. that's the one.

i also found this one:

How to replace transfer case gasket?

just ordered some parts from partsouq

 

[Malcolm99]

Tim goes over it in this video as well, start at 38:30.

https://m.youtube.com/watch?v=gCHSRcq-LP8

 

[BostonJon]

for anyone that finds this later, here's what i ordered:

36108-35060 (oil deflector; first piece on top of the TC housing)
90119-08336 (bolts; not needed but wanted to have them on hand and theyre cheap)
36345-35050 (paper gasket)
36304-35061 (retainer for shift lever; not needed, but inexpensive)
33555-35190 (rubber boot for shift lever)
90521-49003 (snap ring; probably not needed, but wanted to have on hand just in case)

total parts cost was $46, $37 of which is probably not necessary but seemed like cheap insurance in case i dig in and end up needing additional parts




I have a '99 with the j-shift transfer case lever. the parts are slightly different if you have the newer style TC shifter.

 

[BostonJon]

for anyone that finds this later, here's what i ordered:

36108-35060 (oil deflector; first piece on top of the TC housing)
90119-08336 (bolts; not needed but wanted to have them on hand and theyre cheap)
36345-35050 (paper gasket)
36304-35061 (retainer for shift lever; not needed, but inexpensive)
33555-35190 (rubber boot for shift lever)
90521-49003 (snap ring; probably not needed, but wanted to have on hand just in case)

total parts cost was $46, $37 of which is probably not necessary but seemed like cheap insurance in case i dig in and end up needing additional parts




I have a '99 with the j-shift transfer case lever. the parts are slightly different if you have the newer style TC shifter.

I ended up selling the 4Runner because I found a 4th Gen V8 that I couldn't pass up and so I no longer need these parts. Anyone need them? This would be all you need to reseal the J-shift transfer case at the top (where the shifter enters the TC from cabin). PM me

 

[toverturf]

I'm almost certain I have this leak. Either that seal is leaking or it's leaking from failing FIPG. I did have a leak from the shifter but I fixed that and cleaned off the transfer case. Now after a week i'll see a little drip forming right at the bottom of the transfer case where it meets the transmission. It's definitely transfer case fluid as it's clear and not red. I think i'll wait until the fall for it to be cooler before I drop the transfer case and see what's actually leaking.