Just after some advice on oil for these engines. Firstly, im taking it the 2.5 V6 TDi is a "PD" engine? On all my cars in the past I have serviced them myself, I will be doing the same with my A4 - I change the oil and filter every 6,000 miles religiously. When I purchased my Audi last month, the first thing I did was carry out an oil change - I used 0-30 Shell Helix Ultra Extra which complies with VW 504.00 / 507.00. Is this oil ok to use on this engine? (in the past on the service receips 501.01 has been used) If its ok then I will carry on using it - its just that I have heard horror stories with cams being chewed on PD engines. Thanks!