I spoke with the diesel mechanic a few days ago. He told be they would do a diagnostic ($185.00) and tell me what is wrong. i told him the truck is 27years old and the diagnostic will tell him nothing.
It is either the oil pump or it is the sending unit. If he replaced the sending unit on a 400,000 mile engine, it likely will need it soon at any rate. If that doesn't solve the problem, then by elimination, it is the oil pump. So pull the pan!
Old school logic.
His response was they have a procedure from which they do not deviate.
I related the story of a shop that told me, via their diagnostic, my engine light was not because of the alternator but because the third cylinder was dead. There was a tell tale vibration on could feel. Sitting in the truck with the engine running I told him that "vibration" was typical of diesels and was the same as the day I had bought the truck brand new. I kicked him out of the cab and drove it home, replaced the alternator and "walla" the "E" light vanished.
And, the gauge on the dash now read 14 volts.
"Please" I said to this young new school mechanic, "Just fix it"
So, today I got a call from the shop that it was indeed the sending unit and my truck will be ready Monday. No charge for diagnostic. Just the new part and labor to install it.
