2008 Tacoma feeling weak

Having a hard time pulling my boat.

Here is my issue. I bought a 2008 Tacoma, V6, 2 wheel drive (keeping it as simple as possible for low maintenance). Had 21K on it when I bought it.

It has 41K miles and just got new iridium spark plugs put in it because it was feeling a bit weak.
Only put synthetic oil in this truck. Air filter is clean.

This trucks engine "shudders" when loaded up and I first take off.
When pulling the boat out of the water (its under 4000lbs, not heavy), it really struggles.
Now-a-days its REALLY struggling. Its on the verge of stalling as I pull my boat out of the water.

With a 6500lb towing capacity, I find it a bit surprising.

WHAT ELSE could be causing weakness??? There is no check engine light on.

When I first got the truck.... it was sufficient to pull the boat... it would pull it out SLOW... and climb the ramp slow, and it felt like it was a little difficult for this truck, but it wasnt sputtering and sounding like it was on the edge of stall. I keep the AC off when pulling too.


Any ideas? I needs just a little more pep.

If it gets any worse, its not going to work for boat towing.

 

No CEL is on/flashing.

 

You might want to re-check the plugs to start with, and also make sure they are the proper spec for the gap. But it could be several things.... It could be something small and simple that causing it to run crappy and make it feel like that. I shouldn't be falling on its face from a stop, that's where this engine is supposed to shine. Bad injectors? But yeah that's not normal either way. Something is up.

 

The plugs are brand new and I had a trusted mechanic put them in right in front me.
Didnt seem to have an effect. The truck is certainly not worse, since they new plugs were put in.
I was just hoping they would have helped a bit.

Anything easy I can try before having a mechanic look at it?

 

Going out on a limb here, but fuel pumps are known to go bad early on. Could be a possible place to look.

 

When is the last time that you changed your oil? What weight are you using?

Is the shuddering a pinging or something else?

What type of gas do you use?

 

If opp specifically notices the shuttering, what are the odds of it actually being trans related, like stuck in a high gear, etc...