Now down gearing

[Buckes]

My 2000 A6 estate automatic will not down shift unless I use the trip tronic box whats going on ??

[Steve Q]

My advice would be to get a diagnostic check carried out to see whst fault codes flag up. Also I Know with the S tronic gearboxes if you don't get the oil changes done then this can affect the gear changes. Unsure if this applies to the tiptronic box though. 

Also it could be the selector module which is failing.