Over the last month or so since buying my 05 plate 2.0 tdi I've been collecting parts to change the chain driven ballance unit to the gear driven one. I bought a 'reconditioned' ballance unit from this seller Reconditioned oil pump Audi VW Seat 2.0 TDi 140BPH | eBay and the rest of the parts (gears etc) from Audi them selfs. I took the car to a specialist in Blackpool called volkservice yesterday and they said they would get to it ASAP. Today I got a call saying they have rebuilt the car and on starting it the oil pressure warning came on the dash and they suspected it's the ballance unit, so I requested they stripped it back out and check it. Upon inspection they were correct the hex key drive had stripped. I told the seller this and now he is back pedalling saying its the garage at fault, or there is a problem with the oil pressure switch which was not showing any fault when the car was dropped in with the garage. Ive now sent my old chain driven unit to powermax engineering for them to work their magic on it and completely rebuild it and modify it to accept the gear system. When I get my car back I'll give you all a full review on powermax and volkservice but please at all costs avoid this ebay scammer.