A week too late
 

So decided to spend some much needed time and money on the Audi before winter. Caught up some some maintenance and detailing. Oil change, new tie rods, inner and outer, exhaust clamps. Fixed the sun shade, lumbar motor cables. Wash, clay bar, buff and ceramic coating. Polished and wrapped the head lights. Even replaced the missing bumper bolt, was gone when I bought the car. Put a new to me set of A6 wheels with near new continental tires. Drove for three days and yesterday on the way home the transmission shifted hard, shuddered and went into limp mode. From my reading broken drum due to the shift solenoid allowing too much pressure by. I was pushing my luck at 180k, but had changed the fluid at 140k and had some good years. Now trying to figure out what to do with it.
https://cimg3.ibsrv.net/gimg/www.aud...1b0286e99.jpeg

Sorry to hear that/ I do not think it's a solenoid, I think it's the spring loaded pressure control valve. I've replaced this valve in both my D2s with the TransGo kit:
TransGo 5HP-24-PR

It cleaned up the scary shifts in my cars and at least so far I have not had a trans failure. It won't fix blown seals or broken drums that result from the sticking pressure control valve though, only prevent.
I have about 20K on my A8 since I installed the TransGo valve, my S8 I do not drive as much.

Where is a trust worthy place to buy this? How long (time) does it take to install it? I would be paying my shop to install.

I got it off Amazon. Maybe an hour to install if you have a lift and know what you are doing, otherwise two hours. It involves a fluid and filter replacement, pan gasket as well. You need a short T27 bit and some finesse to get a couple of the pan bolts out on the PFL or S8, the cat converter is in the way (the FL A8 pan bolts are clear). See the audipages.com trans filter replacement write-up for details. I did not have to grind a bit but was able to use a bit and 1/4" wrench. And finesse.

This valve won't fit a trans where the valve body has already been reamed out for the oversize Sonnex valve as some rebuilds already have. Also in my S8 despite the relatively low mileage I decided the lower valve body casting was pretty worn out and so I replaced it for $150 or so, that is a little more involved as you have to swap over more valves from old to new. Replacing that VB would also allow for the TransGo valve to be used in place of the Sonnex. In my case I felt the car with under 100K on it deserved the new VB and it was inexpensive, mostly my labor, so I replaced it. The lower VB in my A8 seemed OK at 165K when I put the TransGo vale in. I am not at about 185K on that car.

Be sure to get the right trans filter, round pickup, short (3/4") neck, the 1" is too long and the oval pickup does not fit the D2 pan. Also if you end up with a soft silicone trans gasket IMO throw it out and get OEM or Meistersatz, Meyle, OEM-style.

-Joel.

Perfect. Thanks for the reply and additional heads-up.

Eriksson:
https://www.audiworld.com/forums/a8-...ement-2944722/

If the old-style pressure valve hung up and blew the A drum snap ring groove out (often on a full throttle blast), any of the new-style pressure valves won't fix it, as Joel (jfrahm) said. Fixing the A drum requires pulling the trans and disassembling very much of it. You could change out the trans. The Audi stealership wanted $8000 to get my cousin's 97 A8Q fixed (replace the trans). I got the car for $100 and fixed it. Real big job, labor-wise. Then you'd want to do the pressure valve to keep it from happening again.

You have any fault codes? By limp mode you mean 5th gear and reverse only, all PRND432 lit? Accelerates really really slowly but runs fine cruising on the highway, except no downshifts or torque converter lockup? Never gets normal shifting? That would be a bad sign.

All signs point to the rebuild. No sense in paying to have a shop to do it as the car is not worth that much at 180k. It is too nice to take to a junk yard. So at this point I'm weighting my options. Figure I will pull the tranny and then make a decision. Maybe part out. Maybe strip the car down to the aluminum and steel bits and scrap that way. Sell off some parts. Etc. I have an extra car so not in a rush and I've always wanted to rebuild a transmission. Again if it had died before I spent weeks cleaning, repairing and replacing tires. I might have just dumped it at the scrap yard. My main concern is going down the rabbit hole on might as well repairs if I pull the transmission.

Listed the fog grills on Ebay https://www.ebay.com/itm/223175380844
I will most likely not get around to using them.

Going to sell, part or scrap the car. Let me know if you need anything.