Toyota Repair: toyota special service campaign, vin numbers, pin replacement

Question
Is there any difference between a recall and special service campaign.  i just purchased a '94 4runner, V6 automatic, vin# JT3VN39W2R0138379, (Japan).  About an hour into trip home, i noticed an increasing ping and some knocking going on.  All fluids checked, no engine light.  Engine feels weak.  Other than that, trip ok.  My neighbor has same truck and they just had (March,2006) engine work done by toyota for same symptoms, vin# JT3VN39W1Rxxxxxxx, somehow at toyota expense.  Do you know anything about this?  I asked toyota dealer if any outstanding recalls on this vin# and they came up with only a steering pin replacement.  Also, i'm going need a bunch of help with this truck, can you move next door?

Answer
There is still a special service campaign in effect but I checked your VIN# and it does not apply, the SSC was for a headgasket problem that involved certain VIN numbers, not sure why the pinging etc is going on, the open SSC is for the steering relay rod replacement so you should have that done at no charge to you. Have the dealer check what the problem with the engine may be, I can't move next door but I can help with any problems you may encounter( unless you buy me a house next to yours)