I have a 87 v1500 jimmy 4x4 that has blown 3 oil pressure sending units in the past 2 months. What would cause it to keep blowing?

Physically blown apart to cause a leak or electrically blown?

It starts spraying oil out of the top of it where the wires connect to it.

So to cause a leak.

Genuine GM part or aftermarket part? If you have been using aftermarket parts try a genuine GM part if available. It is also possible that the oil pump pressure relief is stuck causing too much pressure, blowing the sender. Does the oil pressure look normal when the sender is not leaking?