Preventative maintenance, auto transmission and throttle bod

[Soundmangaz]

Hi all, first time posting, apologies if wrong section etc etc...

I have two issues currently bubbling under with my car:

So, recently bought a 2000 volvo v70 mk1 (my second one after my first gave up the ghost). It has 110,000 on the clock and it pretty well looked after and maintained. Thing is, i'm starting to notice a couple of slight lumpy gearchanges from the auto box (yes it's the aw55 5speed with all the issues). And also, unrelated, the car will stall after 5minutes of sitting at idle.

So, preventative maintenance time.

Gearbox: do you think a thorough flush (gibbons mehtod) would do the trick, or should I be looking at gearbox software updates too, and if the latter, do volvo dealers still do them, or anyone in and around bristol able to do them?!

Throttle/stalling: i'm assuming this is a throttle body issue, and that at some point it'll get worse and i'll have to replace it, or am I barking up the wrong tree, could it be a sensor on the way out, the maf or the o2 post cat for example (did the pre-cat when I got it due to eml).

Oh and no messages stored in the obd, except a too lean message whilst I was checking it as it stalled (i'm assuming this was an effect of the stall, and not the cause....)

Any help much appreciated, I love my old wagon!