Fuel pump issue?

Hello all, Ive been having some issues with my 2010 2.7L 4cyl 2wd (125k miles). I noticed about two months ago that I seem to have steadily lost a significant amount of power, especially in higher gears and now I have trouble getting up to and staying at speed when going up hills.

The truck idles fine and doesn't have any stutter or anything. I had thought that maybe I had poor spark from an old battery (5 years old) so I went ahead and replaced it and threw some new plugs in while I was there. The guys at autozone hooked it up to the OBD and say that I need a new alternator, but its resting at 13.5v after it warms up on idle and that seems pretty normal to me.

I just dumped a can of seafoam in the tank and am hoping that it may shake something loose, but I'm beginning to think that my fuel pump is going on the fritz. That being said, the lack of stuttering or difficulty cranking is making me second guess. I can gas it and it'll rev up, it just will not get up and go in any kind of hurry, like I'm hauling a big trailer something. Also, no error codes. See my plugs below, two of them look to be running a bit lean.

Any ideas? I saw that the damn pump is in the tank and I'd rather try something else before I take the bed off.

 

I'd want to check fuel pressure first and if that's good then backpressure on the exaust to rule out a plugged catyletic converter.
Of course my first step with a low power complaint at the shop is a test drive looking at scan data for a clue where to check first.

 

I'll give the pump pressure test a go. Its weird though, in neutral AND in gear I can rev up no problem up to 4000rpm (no stutter, delay, or lunge), but when I'm in gear that rev doesn't translate to acceleration.

 

In neutral there is no load on the engine.

 

Are you saying the RPMs climb when driving but the vehicle speed doesn't increase?

 

might be time for a fuel filter change.

 

Correct, there seems to be no problem building RPM, but there's no power. Once warmed up its not as bad in 1-3 gear, and is mainly noticeable in 4-5 gear

 

Manual transmission I'm asuming?
If so sounds like the clutch is slipping.

 

You know, I took it to the shop to get a quick fuel pressure test done (little local mom&pop shop) and the owner comes in and tells me that its definitely my clutch and that he did feel right doing the pressure test or charging me, what a guy. I got thinking about it and it kind of seems obvious now with the lack of actual engine running issues.

I'm going to grab a clutch kit today and get it done this weekend.