Thread: Trasnfer box sump leaks

Transferbox oil is normally golden when new, turning to black

Autotrans fluid is normally red.

Are you sure it's not the autotrans output seal leaking?

Originally Posted by kelvo

Transferbox oil is normally golden when new, turning to black Autotrans fluid is normally red. Are you sure it's not the autotrans output seal leaking?

I use tansmax z for auto box and the colour is yellowish colour so I dont think its from auto box.

Hi Dearot,
If you have "red" ATF oil in your transfer case I believe you have the wrong oil in it. The right oil is a 75W-90 which is usually golden in colour (should be). The ATF oil is a lighter weight than the 75W-90 which would mean if finds places to leak easier. The two places prone to leakage are the two through drilled holes into the transfer case cover plate that are below the normal oil level and the central shaft O-rings which can be partially seen between the transfer case and where it joins the back of the gearbox on the passengers side of the gearbox.

To replace the O-rings you have to take the transfer case off and hope to goodness the hardened shaft hasn't worn the softer aluminium casing. This is my next job actually, prayer mat is at the ready. I use Toyota black sealant on the threaded through bolts on the transfer case cover, seems to work.

Cheers Marty.

FWIW, old stock Castrol Syntrax 75W-90 is red, Redline of most flavours is red.....


It's only dye, including the golden, honey coloured ones.

Agreed, most probably an intermediate shaft leak.
Have done the O ring replacement by sliding the shaft part way out, as well as more recently the bush in the case fix during a full t/case rebuild.
The 'push the shaft part way, pick the old one off and and slip a new O ring on' worked for about 50-60,000km....and it's no where near as easy as it sounds.

Hi Derot,
If memory serves me right there is a "crushable" sleeve on the intermediate shaft that should be replaced, I've done a couple of these O-rings now and not had to replace the sleeve. This is just for info if you decide to go down that track.

Cheers Marty.

Originally Posted by rick130

FWIW, old stock Castrol Syntrax 75W-90 is red, Redline of most flavours is red..... It's only dye, including the golden, honey coloured ones. Agreed, most probably an intermediate shaft leak. Have done the O ring replacement by sliding the shaft part way out, as well as more recently the bush in the case fix during a full t/case rebuild. The 'push the shaft part way, pick the old one off and and slip a new O ring on' worked for about 50-60,000km....and it's no where near as easy as it sounds.

Yes I remember I use syntrax.

Any how to somewhere on the net?

Hi Derot,
Any good BP servo will have Castrol Syntax 75W-90, as mentioned the red stuff is old stock, new stock is the same colour as all the other "normal" oils, BP bought out Castrol. The old Syntax will mix with the new Syntax, same brew different dye as also mentioned before.

Cheers Marty

Originally Posted by rick130

FWIW, old stock Castrol Syntrax 75W-90 is red, Redline of most flavours is red.....


It's only dye, including the golden, honey coloured ones.

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