My v70 mk2 estate 2001 was loosing water but I couldn’t find out where tried radweld and seemed to fix however after a couple of weeks I noticed the gear box was bumping into gear.
checked the water expansion tank and it was full of gunk coffee coloured oily water checked the transmission and when I pulled the dip stick it was full to the top with the same gunk!!!
I did a dump on the transmission ant topped up with new fluid but after a few miles just the same.
my thinking is that the radiator has been leaking into the transmission has anyone seen this before and can it be saved? Thanks

 

You will need a new radiator and a bunch of the correct trans fluid to flush with. Water does not lubricate that trans very well and your trans is already 2x years old.

I don't have much hope for your trans to survive without damage - How many miles on the trans?

 

194000 miles

 

Ohhh - Good luck 200k/water in trans/bad shifting -

Sorry for your possible loss.

(the problem is you put a radiator in, attempt to clean the cooling system that is rotting from the inside out with oil in it , then spend $$$ flushing the 200k trans - and you still might need a new trans on a 2xyear old Volvo, and then replace all the rubber cooling system hoses, which will easily cost more than the car is worth)