1997 6.5 injector pump dilemma

[Paul S]

The Stanadyne DS4 pumps (what you have) typically last 150-250K miles. Most more, some a little less, but it is not typical to last only 40K. This indicates one of two, if not both, things to me. You have a fuel quality issue, or the pumps have been replaced unnecessarily (the root cause not properly diagnosed). The external electronics, on the other hand, are generally less reliable (but still not as bad as many believe). GM's early policy was to replace the pump and PMD (Pump Mounted Driver - the electronic gizmo box mounted on the side of the pump) as a unit, with no real determination of the cause of failure. More often than not, the cause is a dysfunctional electrical system, which causes the electronic injection control and/or driver to fail.

I apologize for having to bug you. My dealer just called me and said the lift pump is bad and the fuel filter needs to be changed again.They want Almost 8 hundred bucks to do that .Sounds way high to me . I found 6.5 liter lift pumps online for under 60 bucks.Any opinion on that price tag ? Thank you