XSeries-forum

Hi can someone tell me in plain English please what the transfer box is/does. I googled it but I'm not really much the wiser. my scanner has picked up an error in Transfer box 'oil abrasion' which presumably means the needs changing in it ?

Smee

All I did was a search on here for 'transfer box' and I got this for location purposes:

viewtopic.php?f=21&t=1460&p=17153&hilit=transfer+box#p17153

Search options here:

search.php?keywords=transfer+box&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

The oil will need changing and resetting after the change with a drive to set

I had already seen the posts but it doesn't tell em what transfer box is/does - is it part of the gearbox or entirely separate?

What does 'oil abrasion' mean ?

Smee

The transfer box splits the drive between the front and rear axles - typically on a full time 4wd it's bolted to the back of the gearbox.

On this picture it's the bit in blue at the back of the gearbox with the extra prop running to the front diff.

Ok, so presumably oil abrasion means that a sensor is picking up the fact that the oil is breaking down/needing replacing? Is replacing transfer box oil easy and what oil spec does it need?

Smee

i had same fault code reading. i purchased a litre of transfer box oil from stealer - about £30 iirc.
fairly easy to diy change but topping up with new was awkward due to the filler hole being above where you could tip the oil bottle to. a large syringe with a long flexi pipe would have helped!

Does changing the oil in the transfer box open itself up to the same potential problems as already documented on the site when changing the gearbox oil. ie all the crap that comes out was basically holding all the tolerances together and putting in fresh oil is not necessarily a good idea? (my car has 114k miles and the oil has not been changed in the last 40,000 miles of my ownership - 2004 E53 facelift 3.0 D Sport)

i dont think the transfer box is anything near as intricate as the autobox. so my belief was that an oil change would be of benefit, same as an engine oil change.
the old oil was jet black and a bit of swarf on the drain plug magnet. but its been fine with the new oil a year later. i cant honestly say its made any difference to anything tho apart from the error message gone.