Does anyone know how to replace subrame , I mean instructions step by step???

Thank you!

 

Try BentleyPublishers.com
You need to support the engine and transmission from above with a beam. Also, you should replace all of the subframe bolts with new ones from Audi. These bolts need to be torqued to specification per the Audi shop manual.
A transmission jack with an adapter made for the subframe may be needed.
The instructions depend on the year, engine and transmission of your A6.

 

okay, I will try to do some more research..

 

What year and model is your car, Rider?

 

This is 2.8 A6 Quattro 2000 model

 

Sorry, I only have the Bentley for C4 (1995-1997). I could give you the step-by-step instructions, but I'm affraid you have a different subframe in your C5 and it would be useless.
Maybe someone else could .pdfed that for you.