I have had a slight leak on my sump gasket since I've owned the car, which has never been a problem, I've just topped it up every few thousand miles with about half a litre of ATF.
My gearbox is the ZF 6HP26 6-speeder and I understand the fill procedure well and have the proper ZF fill instructions, so I understand the fill temperature issues too.
The issue I have is that I can't get hold of the ATF anymore. I used to go to the main stealers with an empty oil can and buy a couple of litres of ATF which they filled from their drum in the workshop. I spoke to them yesterday and they said they are out of stock and won't be buying anymore of my ATF as it is discontinued. They said there is a replacement ATF available by the litre, but they don't advise mixing it with the old ATF.
They suggested I have it drained and refilled with the new stuff. When I told him that half of the ATF is still in the Torque converter and can't be drained at the same time, he didn't understand what I was talking about. Without completely force flushing the 'box, that old ATF is always going to be mixing with the new stuff, no matter how many times I drain and fill it.
I then spoke to another dealer who said "due to health and safety issues, we can not sell you some oil from a barrel, so you'll have to pay £270 for a 20 litre barrel or bring the car in and we will top it up for you".
Does anyone know where I can easily get a litre or two of ATF for my car? or, can I mix the new stuff with the old?
The old stuff is the ZF S671 090 255 Oil LifeGuardFluid6, which I think is manufactured by Shell, having the part number Shell 1375.4 (need to conform this).
Sorry for the long conveluted story, but any advice is much appreciated.