Hi, everyone. I'm new to the forum, but have already read and learned so much. I recently bought an '03 F350 CC 4x4 Dually with a 6.0. I've noticed a disturbing knock, which seems loudest at the top of the rear cover. You can feel it in the oil pan as well. Right after I got the truck, I changed the oil and filter, air filter, and both fuel filters- (All parts came from the dealer.) I took off the turbo and cleaned the rust and carbon out of it. I installed a manual oil pressure gauge and, when cold, there is between 80 and 90 lbs. of oil pressure at idle. I cleaned the pressure regulator and made sure it wasn't sticking. (It goes off the gauge if you rev it.) With a warm engine, there is between 35 and 70 lbs., and there is an odd fluctuation. Along with the fluctuation in oil pressure, there is a rough idle/miss. Anyone have any ideas? Exploratory surgery is scheduled for tomorrow afternoon!

 

Is there a miss timed with the knock?

 

Welcome to the site pal!

How many miles on the truck? Have you run an OASIS report on it? Did it show any motor work?

 

The truck has 138,000 miles on it, and the OASIS didn't really tell me much. (Closed CUDL). There's not a miss corresponding to the knock, but the running quality, at idle and mid-range, has gotten worse lately. I just don't get the fluctuation in the oil pressure. If the regulator is set at 75 lbs., then why is the oil pressure going up to 100 lbs? On the road, aside from the knock, the truck runs strong and smooth. I've gotten no CEL at all. Oh yeah, in addition to all the other stuff I've done to the truck since I've gotten it, I pulled the EGR valve and cleaned it, and I pulled the EBP sensor and tube, and cleaned them both. I think I'm gonna have to pull an engine soon.

OASIS RESULT:
1FTWW33P13ED43684
06/06/2007
23:27:02
FCXWS446
© Copyright 2002-2006 Ford Motor Company. All rights reserved.

VEHICLE INFORMATION
VEHICLE DESCRIPTION
2003 F-SERIES BODY STYLE
F-350 CREW CAB 4X4 ENGINE
6.0L DIESEL DI V8
TRANSMISSION
TORQSHIFT AXLE CODE
61 ENGINE CALIBRATION

WARNING MESSAGES
CUDL - THIS VEHICLE HAS A CLOSED CUDL CONTACT
ARN MESSAGES
ATTENTION TECHNICIANS AND SERVICE MANAGERS:
BEFORE REPLACING FUEL INJECTORS FOR COLD ENGINE OPERATION SEE TSB 07-05-04
BEFORE REPLACING 6.0L TURBOCHARGER OR VGT SOLENOID REFER TO 06-23-02
GENERAL WARRANTY INFORMATION
WARRANTY START DATE
09/15/2003 BUILD DATE
05/22/2003 SALE MILEAGE
00000
OUTSTANDING FIELD SERVICE ACTIONS
NO CAMPAIGN MESSAGE(S) FOUND
EXTENDED COVERAGES
NO ESP INFORMATION AVAILABLE
WARRANTY REPAIR HISTORY
NO RECENT REPAIR HISTORY ON VEHICLE
Click Here for Full Warranty History

END OF OASIS REPORT FOR 1FTWW33P13ED43684

 

The closed CUDL means that there was some type of customer complaint made directly to Ford on your truck, which they are saying was resolved. In my experience the OASIS information is only kept active and displayed for the previous 12 months. This is the info I get as a fleet administrator. Maybe the dealers access goes back further.
Also, just an FYI, I wouldnt cut and paste any FMC copyrighted info here as it is a no no.