Hi guys, so I have had my mechanic take a look at my car because of a rear wheel locking issue when turning sharp corners. He wasn't 100% sure if it was just a simple task of replacing the haldex oil and filter, or if it required to replace the whole haldex system. He's calling me back later this afternoon after he talks to his brother who is an Audi specialist to get his opinion. Would it be worth replacing the oil and new filter to see if it will correct the issue? It will cost me $350 AUD to replace the oil and filter, so I don't want to be spending money on something that doesn't need to be renewed/replaced. If it is the Haldex system i'm guessing im looking at $1000. How do I know if it just needs to have the oil changed? or if it needs the whole system changed? Thanks!