You guys are gonna love this! I had a new customer w/a beat up F550 dump truck in my shop for a few days now and the truck had multiple complaints ranging from starting troubles, low/no oil pressure, eng lights, huge exhaust leaks, coolant leaks....etc. I found leaking water pump, broken Y pipe at the turbo, checked for leaking stand pipes and upgraded them to the newer design while there and replaced the IPR while I had the Y pipe out. Truck still was experiencing slightly longer cranking times than usual but would run with a slightly noticable decrease in power. With the motor still somewhat apart, I did some more checking and troubleshooting. I pulled the oil filter to check the drainback valve......and it was gone
! No lie, it was not there at all
. Customer stated that the truck had been difficult to start for well over a year or 2!
He replaced 2 turbos due to bearing failures and he said the other 3 trucks he had w/6.0s seamed to run stronger. Basically, the oil pressure light was on due to, LOW OIL Pressure!
It ran like crap b/c the injectors didnt have the rail pressure required for complete injection and the turbo failed several times b/c the bearing was deprived of sufficient oil supply. This customer has his own mechanics in house but brought it to me after others tried but they couldnt figure things out after wasting many $. Amazing huh?
Essentially, the underlying cause resulted in thousands wasted... over an $8 plastic valve! Hope this never happens to anyone reading this. I have no idea how many hands were on this motor over the years or how long this truly went on for? The 2004 truck had only 51,000 miles on it. Beware guys. There are so called "mechanics" out there working on trucks, doing things just like this!
Forgot to add others had replaced: 8 injectors, egr cooler and valve, HPOP, and catalytic converter in an attempt to remedy this trouble!