While driving at about 75 mph around the M25 to Gatwick Airport at 5.10 this morning I hit an 'unidentified object' lying in the middle of the carriageway. Several loud bangs later and the oil warning light in the DIS immediately started flashing so I pulled over to the hard shoulder at which point the rest of the engine oil was deposited. From the less-than-one-second glimpse I had of the object it was probably wooden and about 2 feet wide and 1 foot high. Needless to say the privatised Motorway Maintenance guys didn't exactly look hard for it when I reported the problem to the Motorway Control Centre. Anyway, the car's now at the accident repair centre waiting for the insurer's engineer (insured with Tesco) to have a look at it tomorrow. The guy at the centre says it's a minimum of a replacement sump and quite possibly a replacement engine. Fortunately it's fully comp so it will only cost me the £150 excess, but out of interest do you guys know how much a new sump/engine replacement would be? What are the implications of this work and what sort of questions should I be asking about the repair? Any help appreciated, thanks in advance.