Help....what grade oil do you guys use in your evo's?
 

I recently acquired an evolution 6 which has and evolution 8 engine roughly 3.5 months ago. Fast fwd to my first service.
I serviced my car using mobil 1 10w30 full synthetic oil, genuine oil filter, and put in ngk laser iridium plugs. checked the transfer case, diffs etc. however two days later while cruising in town my car lost compression and i pulled to the side of the road because i was concerned. I noticed a faint sound which sounded like a knocking in the engine. I immediately shut off the car. I ended up putting it on a wrecker. The next day i was told that my engine had seized? upon dismantling the engine, it was discovered that the no.1 rod had fused to the crankshaft. Now i'm told that i need two connecting rods, bearings and a crankshaft. My mechanic said he suspects the engine oil, however he has no scientific proof to back up his views.
Note. this engine was inspected by him 3.5 months prior, he said he had checked the engines bearings etc before putting it into the car. he said everything appeared in good condition.
Point to note, the engine was stock, running stock boost levels
My questions are:
1. has anyone had any similar issues with the type of oil in their 4g63T?
2. any idea what could have caused this?
3. my mechanic says that he doesn't recommend this grade of oil, does any one agree?
4. I'm under the impression that something might have been wrong internally with the engine.
5. can anyone shed some light on this issue?

I don't remember the exact oil requirements for the evo8 engine but it is either 5w or 10w -30, using either one will not cause engine damage.

I've looked this up a few times before and it seems alot of guys run 10-40. Supposedly its easier on the bottom end but harder on the head. As one guy said "I'd rather rebuild the head than the block."

thanks guys, much appreciated.