clunk comming from rear end is the tailshaft rear uni joint, get a new one, simple test to see if that's it, put car in neutral, put hand brake on, and chock the wheels, get under the beast and with both hands on the tailshaft, try and spin it, if it moves even the slightest guess what, new tailshaft uni's needed. i wouldnt try to do this yoru self, those little things are pressed in by a little machine. some peole use hammers to bash them into place, unless it's done properly, you can do some serious dammage, worse case, cause the tailshaft to fly off, and basicaly flip the car on it's roof. as for the car hitting 80k's and loosing power, look under the bonnet, make sure everything is fine under there, check spark, check crankangle sensor, check air flow meter, and check fuel. it will more than likely be one of those things.
get her to pull the dipstick out, after the car has been run for about 10 min's or so, grab auto dipstick and run finger's down it, check it's pink, red and not dark red, like blood colour. if she has any black residue on her finger's, guess what, gearbox buggered. as for the car not going into reverse for a while, it sounds like it might be slipping, get it serviced, they will replace oil, filter, and give the bands a quick tighten, about $90-$100 for that, the 2 bands in the vl box are a abspestos supstance sitting on 2 very strong plastic thingy's, (cant remember the name,) they will tighten it, but be carefull though, if they open it up and there is even so much as a little hint of metal on metal wear, they can tell from the bottom of the pan, you will be looking at a new gearbox, a new box for a vl will set you back around the $1500,00 mark, had the same problem with the oldgirl in the back yard now, she wouldnt go into reverese straight away, and it would take about 3 min's of running in 1st before it would kick into 2nd, then drive normaly. new gearbox was needed, so i went and converted it from auto to manual, by far the best option. more expensive, but i can work on the manual, not auto, they are a hydrolic membrane on those things, very scary.
hope this helps you, but from the sounds, your girlie will be spending a heap of dollars very soon.
cheers
garth
