Truck Is having major issues

[jeffro22]

towed a 9000# boat down from SC to the FL keys for vacation.

On the way down the truck started to give me some issues. First I started to notice a slight loss of power. Then my fuel pressure started to drop and I had a real hard time keeping the truck up to speed . FP kept dropping and falling below 40PSI according to my gauge. Stopped to inspect and found the gauge mounted inside the engine compartment with my regulated return system was broken. We were able to remove the gauge and replace it with a plug . (the glass wasnt broken but the needle had broken off)

truck seemed to do better but still not 100%. i was able to feather the gas pedal enough to maintain a decent speed (65 mph) and keep FP abopve 50 psi for the rest of the way down, but if I give it alot of gas the fp drops way down!

Also, I am losing coolant internally. We had to add a couple gallons to the system on the way down and can tell the truck has been puking a lilttle and is making a slight whistle sound from the degas bottle.

truck does fine without a load and FP stays right a 60psi, but when I try to pull the boat the FP drops quickly and power is an issue?

I did have a bunch of work done lat year (head studs and gaskets) but it seems like my HG's are going again.

Any thought sor tips is greatly appreciated. I still have a 700 mile trip back home I need to make at the end of the week.

[PGreenSVT]

Clogged oil cooler and blown egr cooler are good possibilities. what is your coolant temp and oil temp delta.

[jeffro22]

i dont know as I dont have a way to check those temps.

However, The EGR has been deleted, and the oil cooler was replaced about a year ago. i have been running a coolant filter also.

Any thoughts on why the FP keeps droppping