Water and oil mixing on ZF6 autobox

[Disco beginner]

I am in the process of installing a Audi 3.0 V6 TDI engine and ZF6 HP19A automatic gearbox into my D2 but when I drained the water of the audi's radiator milky water came out and upon further inspection even more milky water came out of the autobox so the cooler in the rad obviously packed up. Now my big question is I assume a flush will not be sufficient for long term reliability or will it be fine with only a flush or will the box require a rebuild?

[Commander]

Sounds like an interesting build, can you share details? I suspect it will be quite a challenge to get all the electronics to work, but those motors are really quite fantastic.

Unfortunately I don't really have input to provide on the gearbox question, I don't recall hearing of the oil cooler failing (at least not a common problem as far as I am aware), I suspect it would depend on how long ago it failed and how long it was driven like that. Potentially the pressure in the box will stop water from flowing in but allow oil to flow into the radiator. But I don't know for sure.

[Commander]

I checked in with Stephan v Tonder (one of our local Audi/VW specialists) and he recommends doing an oil flush on the box and perhaps also dropping the sump and inspecting the valve body to make sure it is clean. Be sure to use the right oil and also check for correct flush/fill procedure. Some of these boxes are pretty sensitive to both those items.

[Orxy]

Interesting build, it would be nice to know where you sourced the electronics and gearbox adaptor plates?

Did you consider the BMW diesels? They are extremely popular in the UK, to the extent that there are plug-n-play kits available for the ECU and gearbox adaptor.

[Disco beginner]

I checked in with Stephan v Tonder (one of our local Audi/VW specialists) and he recommends doing an oil flush on the box and perhaps also dropping the sump and inspecting the valve body to make sure it is clean. Be sure to use the right oil and also check for correct flush/fill procedure. Some of these boxes are pretty sensitive to both those items.

Thank you. yes the box has stood with this mixed cocktail for a long time so don't think I can trust it, and rebuild is around R40k so not an option I have bought another donor vehicle Q7 with 3.0 tdi so I will use the oil pan and gearbox from the Q7 rather which has a stronger aisin autobox which I never knew before always thought they also had the zf6 gearbox I now obviously need to pull the wiring and sort it out to transfer it over to the D2. I have taken a few pictures and when done will see if I have time to do a write up on it

[Disco beginner]

Interesting build, it would be nice to know where you sourced the electronics and gearbox adaptor plates?

Did you consider the BMW diesels? They are extremely popular in the UK, to the extent that there are plug-n-play kits available for the ECU and gearbox adaptor.

I will design and build my own adapter plate that will mount the 6 speed auto to the transfercase. I will use the original electronics. Yes the M57 conversion was my first idea but the v6 diesel is a shorter motor that fits great and gives beter power delivery and fuel consumption

[thabogrobler]

Wow!

This will be a very interesting build!

I guess the D2 does not have too much electronics but how will you handle stuff like speed input, abs, etc with the original ecu?

[Disco beginner]

Wow!

This will be a very interesting build!

I guess the D2 does not have too much electronics but how will you handle stuff like speed input, abs, etc with the original ecu?

Traction control and abs is controlled through the BCU, the speed signal comes from the transfercase which will be used. So yes there is a few that willl need to be tapped into like revs from crank sensor and water temperature but those are minors what I hope to also be able to do is to make the LCD screen display the autobox functions which will be more complex