I would not put any more money into it untill the extend of the damage is found.
Running the engine without oil can damage main/cam/rod bearings, score cylinder walls and a whole bunch of other problems.
You can try a compression test to see how much cylinder damage occurred. Check the enginge code with a scanner.
The shaking is probably metal to metal contact and cannot be repaired with oil supplements.
You might try some of the oil treatments, you have nothing to lose except the cost of the supplement.
You will prpbably wind up replacing the engine (rebuild/remanufacture/used).
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Wednesday, July 2nd, 2008 AT 5:15 AM