Transmission Issues! HELP Audi A4 B6 1.8T Tiptronic
 

Hey everyone!

I have a Audi A4 B6 1.8T Tiptronic that has been having some issues lately and I am hoping someone can point me in the right direction!

The car has 308,000km on it and a couple weeks ago I had my timing belt snap. While I was in the process of finding out if the valves were tapped I found an engine in my small home town with 170,000km on it for $500. I kinda impulse bought it hahah. Anyways, a friend and I pulled the old one and installed the new one over the weekend. Everything went smoothly and the engine ran well. I lost a lot of transmission fluid while doing the swap, so I decided to drain the fluid and refill it with new stuff, which was not Audi spec fluid because its damn expensive and a friend at Audi mentioned lots of guys run normal stuff with no problems at all. After everything was said and done I drove it down the driveway with power to the wheels but when I pulled onto the main road to take it home I pressed on the gas, the transmission slipped and felt like I was in neutral. The next day we drove to Audi to buy a coolant flange that had a crack in it and talk to a different friend at Audi about the problems going on with the transmission. After talking to him we went back thinking we needed more transmission fluid in the pan to fill up the torque converter. We got back to the shop, put all four corners up on stands, started it up and pulled the filler plug. Probably a quart and a half of fluid came out and it wouldnt take any more, which made me think the transmission wasnt taking any oil up into the internals, like the car was off. We scanned the car after looking at the dash and seeing the PRNDS lit up in red (limp mode) and these are the codes that came up:

P0730 - Incorrect Gear Ratio
P0811 - Excessive Clutch Slippage

When we did the swap the engine with 170k on it came with a TC but decided to put the TC with 308k onto the new engine because TC on the 170k engine looked rusty. Is it possible we bound a gasket or something on the TC when putting the "new" engine in and the transmission isnt building pressure? I dont really think my transmission is cooked because we didnt really touch it or take it out when doing the swap.

Thoughts?

Many thanks!
Luke