I have a 2003 6.0 with 85,000 miles on it 6 speed transmissioion. In November while pulling a 35" trailer I lost all power I pulled off to oth side of the road and replaced the upper fuel filter. This filter was completly plugged and when it was replaced this fixed my issues. I drove this another 100 miles before replacing the upper and lower filters as part of a matched set.
Now the issue I am having is the truck now feels like it is missing when going up even a slight grade. Slight vibration and no pickup power. The second place the problem is noticed is passing a car same no passing power. But the truck runs fine going down hill ior on the flat.
I'm guessing I messed up a fuel injector. Is this a proper assumtion or did I screw something else up. There is no check engine light and I still have original batterries.
Is there anyway to check the injectors or is this a dealer only Troubleshooting technique.
Any help or advice would be greatly appreciated.