Correction: every gear slips.....so I'm thinking this is either because of the loss of hydraulic pressure as Brunswick Garage mentioned, or possibly the torque converter? Or possibly even both, considering the rough up shifts as well.
I tried to give up on this issue and just let it go because of how much of my time and money it's already taken up. But being a technical guy (i do boiler repairs) i just can't stop troubleshooting it in my head

 

I understand, man.... I'd keep my eyes out on Ebay or some of the other Used Audi Parts (I'm not sure what's available in the UK as I'm in the US) for a transmission of the same code. You might be able to get it for a good price and it truly be a drop fit replacement and lot less expensive than a rebuild. Plus if you can get a good used trans, you can drain a LOT more fluid out of the torque convertor with it out of the car. It's damn near impossible to get it all out without cutting it open (not exactly recommended, if'n ya know what I mean). At least you can start out with as much fresh fluid in the used trans as possible. I'm also like you, if the rest of the car is in excellent shape, I hate to essentially junk it out just because of a transmission. Sadly with the costs and complexity of today's cars, and today's throw away society, we're being forced to do so.

 

You read my mind. I've been looking for a replacement box today. I am searching but nothing cheap enough yet (except one with 150k miles on it, which i don't really wanna touch because of the mileage). Another place in Europe wants €1500 for one with 86k on it. But with delivery and fitting, it won't be much cheaper than a rebuild...the search continues.
And yh it is such a shame so many newer cars end up being scrapped early now. Nothing like the old school.

 

I got a couple of new quotes for new gearboxes... £900 for one with 62k miles on it and 3 months guarantee. Or £1500 for a refurbished box with 12 months guarantee... Add the fitting costs to that and I may as well pay a little extra and get my current box refurbished....which is still too much to spend on this car.
So then I called the guy with the 4.2 engine and asked if he has this gearbox...he quoted me £550 for the gearbox AND fitting. With 1 month guarantee....but (when it sounds too good to be true, there's always a but), for one, he's 200 miles away (I know, I'd be crazy to go). And secondly he said the mileage on the gearbox he has, is 100k but he doesn't have any proof of this. And when i asked him about the 4.2 engine and gearbox some days ago, he said the same thing...100k miles, but no proof.... so I'm now stuck with my head telling me to let it go but my heart telling me to find the best way of going ahead with this, without screwing myself again.
If I do decide to do the stupid, I guess my best bet is to equip myself with as much knowledge of inspecting a used gearbox as possible before i leave (and waste about 6 hours of driving and about £100 fuel if it turns out to be crap...although if he's fitting it as well, he can't get out of his guarantee if anything goes wrong after fitting). And it's still cheaper than my next cheapest option which is to fit a gearbox from eBay that has 149k miles on it.
If i do install a used box though, I would also want to go over the valve body before installation....including a new separator plate and testing solenoids from both valvebodies and keep all the best ones.

 

100K miles on these engines and transmissions is nothing. I've got over 200K miles on mine and no issues. Just need to keep oil in them. LOL

 

Yeah I know mate, It's just my car has 99k on it, with an audi main dealer transmission service at 31k and now this service at 99k. I know there is room for one more service in between, but still...once bitten twice shy.
Plus the guy quoting me £550 all-in doesn't seem to care too much. Seems like he's getting bothered by answering questions about his product and he's just throwing a random number out for the mileage because there's no way to prove it. He did the same thing when I asked about the 4.2 engine, and just happened to throw the same number at me then as well....100k miles. So I can't trust his word. And all in all, his transmission, fitting and the trip would cost me £650-700. Whereas I could get the gearbox with 149k miles on it, which has been tested and has 60 days warranty, for around £400 (there may be room for a little negotiation) and I've now been quoted £250 for fitting which is pretty cheap, but the mechanic who quoted me for the labour is recommended and local (ok, its the other side of london, but London is small....its the traffic that makes our journeys long), so i'd be ok with it. Add a local journey and maybe an extra litre of fluid (my current fluid is new so i'd be looking to reuse that and the filter), I'd be looking at around £700. And I'm hoping to get a whole set of good solenoids between the two boxes as well, otherwise there is the potential (but unlikely) cost of that as well.
Now take that, minus the 400 miles and 6 hours of driving time and you have my currently preferred option..

...do you think I'm over thinking this yet? Lol

 

Probably but... LOL

You might could reuse the fluid but remember the fluid change only replaces about half of the total fluid that's in the transmission. The new filter would clean it a little but it will appear a bit dirty when you drain it since it's mixed with the old fluid. As expensive as that stuff is, I'd be inclined to recover and reuse as much as I could too.

 

Agreed. Would prefer all new fluid, but another £332 for the same thing i just bought (I gave the mechanic 10 litres of Audi fluid and didn't get any back, so he must have done a full flush...or screwed me....one or the other) would feel like insult to injury at this stage....on a funny note, we seem to be on the same page about quite a lot...glad someone understands. Lol.

 

I think I used about 7 liters on mine the last time. I got a couple of extra just in case I had a "user" error and spilled one.. LOL I was handling that stuff like Nitro Glycerin in a Western Movie when I was refilling the trans.... LOL

You could filter the drained fluid through a funnel with a couple of coffee filters in it to filter out any dirt buggers that may have fallen off the transmission during draining. I've filtered coolant this way for years.

 

Oh wow...coffee filters...I've been thinking of how to filter the current fluid but that didn't come to mind. You're awesome, Dave.
Which has me thinking. I've booked the car in with a gearbox specialist just to check the fluid level...I want to be sure the job was done correctly. Now I've found something online called Lucas transmission fix (bare with me) which is solvent free and helps with friction on clutch plates and it thickens the fluid a little. I'm considering asking the guys checking the fuid to add this while they're at it...considering the contents of it, and the reiviews, it can't hurt and it has helped in a lot of people's cases, who didn't have a lot of internal damage to their transmissions. And worse case, I'll be changing the transmission in the end anyway. And I'm also thinking if the old fluid that was removed when I had the service done was thicker, which prevented some hydraulic pressure loss within my transmission (baring in mind almost no metal debris came out in the sump), then this additive thickening the current fluid may help the transmission go back to its previous state, where only the upshift from 2nd to 3rd was jerky (I realise there's a lot of hope more than anything else involved here, but considering reviews on the product, my fingers are still crossed).
Now for the real debatable bit....if after that it still comes down to replacing the transmission (as I expect it most likely will), when reusing the current fluid in the replacement box, I will now be reusing fluid with this additive. And in doing so, I can only go off what Lucas claim from their product....it can also be used for preventative maintenance...so that should be fine. Either way, I most likely will be using thiis additive in my current transmission because I've got nothing to lose...and if I do, I'll let you know how that goes.