This is probably a stupid question but how do I check the fuel pressure on a 2006 f350??

 

there is a test port on the upper fuel filter housing

 

There isn't a factory-installed sending unit to monitor fuel pressure, so you have to add one. Typically a 2" electronic gauge is the easiest and cheapest way to permanently monitor it from inside the cab.

Inside the engine bay, there are two black plastic caps, one is the oil filter and the other is the secondary fuel filter. The fuel filter is the rightmost of the two, and down on the side facing the driver's side headlight, somewhat hidden behind a black radiator hose is an oval housing bolted to the fuel filter housing. At the very bottom left of that cover is a small brass plug with a 6mm head ( it's hard to see at this angle, it's easier with the intake removed), and that is the fuel pressure test port.

There are a few common ways to install sending units; directly into the filter housing using brass fittings, using an extension of fuel line to relocate the sending unit, or an aluminum replacement cap with a tapped port on it.

An easy way to hide a single gause is in the dash cover by the steering wheel (one will fit on either side with some cutting, if you have the Lariat info center buttons in the way):

 

reps to you Bryan very good description Thank you. This is the next project for me as soon as the truck feels like it wants to start again.

 

Yes as stated the best way is to use the test port and the adapter hose you can see the test port here Page 30: Fuel Supply System
Fuel pressure under 45lbs at WOT will kill injectors and over 75lbs at idle may blow injector o-rings mine with 17k had 44lbs at WOT and 50lbs at idle installed the new fuel reg spring now 58lbs at WOT and 62-64lbs at idle and this is the way i went
, This is a cool set up gets the sender away from the heat and viberation of the motor.

6.0L Fuel Pressure Adapter

Column Pod
http://shop.strictlydiesel.com/store.php/products/15010
Autometer Fuel Pressure gauge---Bottom Left (This matches my Dash gauges)
Phantom II Gauges
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