Transfer Case Cracked

[Charlie]

Guys,
Just giving my truck a service after returning from Morocco last month, and found a leak from the transfer gearbox. Upon further investigation the oil leak is coming from level plug / cracked housing, is this housing easily changed in situ or will I be better off removing the transfer box assembly first before changing the cover?
I can only assume the last person to check the oil level over tightened the plug, causing the casing to crack…

 

[Chris]

Charlie, you say the leak is from the level plug? Then it can only weep a little when the vehicle is moving and the oil sloshes around. It's under no pressure or anything. I would really be tempted to clean it up well, abrade it slightly and go with a liquid metal filler compound to seal it. Removing the T case is not a 5 minute job and it's damn heavy too. Not quite sure what you mean when you ask can you change the housing in situ or would you be better removing the whole unit - they're one and the same thing aren't they? Working only from memory, the filler plug is in the main body not the rear extension housing.

Chris

 

[Charlie]

Chris,
I was almost thinking along the same lines regarding the metal filler compound, I will probably go that way.

 

[J66P]

nothing to loose thats for sure

 

[Chris]

I think that if it were me and it was on my drive (I'd probably stick my spare box in ) I would just go with a simple repair, yes. If I wanted to play around, I might machine up a threaded sleeve which I'd 'glue' into the hole and have a smaller filler plug in there. But only because it'd give me something to do.

Chris

 

[Jon Wildsmith]

Is that an OEM washer? The OEM ones are hollow and don't take much force to make a seal. The crack will go right through to the plug thread so as well as sealing the crack on the outside you'll probably need to use sealant on the plug seat each time you disturb it.

 

[Chris]

It doesn't look right to me Jon. I was thinking that there was a recess on the mating face and the OEM washer fitted inside that - in other words you can't usually see the washer. If the washer were too big, it would put pressure on the outer edge, possiblyleading to the crack. I shall have a look at the one under the sheet outside tomorrow. What you don't want to do is keep flexing the crack every time you tighten it up. I might be tempted to use a fibre washer instead.

C

 

[clivehorridge]

It doesn't look right to me Jon. I was thinking that there was a recess on the mating face and the OEM washer fitted inside that - in other words you can't usually see the washer. If the washer were too big, it would put pressure on the outer edge, possiblyleading to the crack. I shall have a look at the one under the sheet outside tomorrow. What you don't want to do is keep flexing the crack every time you tighten it up. I might be tempted to use a fibre washer instead.

C

I had the same thoughts, the copper washer seems to be caving in as if it should be smaller and sitting in a recess. It appears to be trying to spread the threaded hole outwards, as already said, encouraging the crack to form and widen over time.

Would it be worth trying to cut a narrow saw-blade-width slot straight down the crack and filling it with plastic metal. It would give you clean fresh faces for the plastic metal to bond to and the plug could be replaced to maintain the thread profile while it goes off hard.

Just a thought.

 

[Chris]

I pondered that one myself Clive, but thought any 'chopping out' would best be a vee to the outside so that any compound would be pushed into the gap rather than be allowed to fall out if you follow. And then I though, it's such a small crack, I'd blast it with brake cleaner or something volatile and then simply squeeze the repair material in. You could put a jubilee clip around to pull the edges in, but I think that it would flex. Better to fill it as it is I think. You can always go to plan B later. If the plug is then slightly slack, you could put a wind of PTFE tape on there. it's only a weep at the end of the day and as long as the breather if clear, a smudge of filler should sort it. To be fair, I should think that RTV would stop it leaking and be flexible. With the correct washer, the pressure should be off the outer rim of the boss.

Chris

 

[Charlie]

For the last couple of years maintenance has been carried out by an independent Land Cruiser specialist, but I am beginning to lose faith in the company right now. After I have replaced the current plug with a new plug and wash from Toyota, I will clean the area up with contact cleaner then seal the leak up with a metal filler compound.
Any recommendations on the brand / type of metal filler compound?

 

[Chas]

For the last couple of years maintenance has been carried out by an independent Land Cruiser specialist, but I am beginning to lose faith in the company right now.

Any chance we will learn who this independent Land Cruiser specialist is?

 

[Charlie]

I want to talk with them first, it would be wrong to not allow them chance to put the situation right.

Any chance we will learn who this independent Land Cruiser specialist is?

 

[clivehorridge]

Tend to agree with you Chris, on second thoughts, as long as it can be cleaned well before filling. I suppose Plan B should always come after Plan A!

 

[frank rabbets]

This is what to do. Remove plug and degrease. Degrease the crack and apply loctite to the plug and crack. Loctite will fill quite a big gap. Loctite has amazing capillary action before it goes off. Use a thin copper washer or none at all. To ilustrate loctites creep action you can put a nut and bolt together and apply loctite after.

Frank

 

[Jon Wildsmith]

There is a tapered recess iirc and the hollow OEM washer is shaped to fit that with little force needed. They are cheap and supposed to be replaced every time you undo the plug but if you don't do them up too tight you can get a couple of goes out of them. Something more solid being squeezed hard against the tapered surface certainly seems like a recipe for causing a crack like that.