Power and shift cable problems

[snagglepuss]

Have a 2004 F150 (222 hours) that normally will give me 5400 rpms, but it suddenly will only record 4700 rpms at WOT. Today I noticed it dropped to 4600 rpms but will not give anymore as the trottle is pushed to the end. I also had an issue today where the motor would not shift into reverse--it would grind as I pulled the trottle back and would start to rev (like it had no reverse)--this occurred when I had the motor tilted up. This happened about 7 times--finally got the boat turned around and headed into deep water where I could put the motor down but it still wouldn't shift. After running forward about 40 miles it did shift into reverse at the dock. But I'm scratching my head on these problems. Is it possible that the trottle and shift cable needs adjustment? Is this an adjustment that is relatively easy?
Thanks

[boats.net]

You can check that the shift linkage on engine is set in neutral properly and travels fully in forward and reverse position and same with throttle.

[snagglepuss]

Thanks for the reply, moderator. I re-read my question--you must think I'm retarded spelling throttle 3 times trottle. Must not of been tinking straight that night! I will check out your suggestion. Thanks. Do you think this could have anything to do with my WOT problem too?