First, don't have a flushing change done on the gearbox ATF - not at that mileage when it appears to have never been changed!
It's likely to blow the seals internally.
Instead, if you're having a garage do it, get them to do a "sump-dump" change - drain the contents of the gearbox sump, refit the drain plug and then top up with fresh fluid to the correct level.
Repeat at monthly intervals until the fluid stays clean. Usually 3-4 of these -art-changes does it.
You'll have the AW30/40 or 30/43 box in it, if it's the 40 the stall speed is 2700rpm and if it's the 43, stall speed is 2100rpm. Out of all the boxes fitted to the 7/9xx cars (and the V70 is a development of them) most are about 2100rpm stall speed - pg 101 shows this on this pdf :
http://www.myvolvolibrary.info/Tech_...DataPocket.pdf
Oddly couldn't find a listing for the B6304S, i know they ade one so maybe i need to find another Data Pocket that lists it.
I've just typed all this and realised you said V70 - that's the FWD jobby isn't it?
I'll try to find more specific data on the box you're likely to have and data on it. The sump-dump advice still stands though.