I have a 99 5.4L, and my buddy and I do a lot of tourney fishing. What are the best performance upgrades, particularly for towing a boat?

 

Prolly just gears.

 

x2 on gears.

Beefy trans.

Upgraded brake system.

What does your boat weigh? A 3,000 pound boat is hardly noticeable behind stock w/ 3.55. Personally unless you have some 28'+ foot monster I wouldn't worry about upgrading anything. Use it until something breaks. You might be surprised if nothing ever does.

 

A tuner with better shift points might get you where you want to be for cheaper than gears if this is a DD too.

 

It's just a 20' bass boat, but I've pulled it a few times, and the truck always gears down and runs at about 2800 RPM until the ground levels or declines. I had the same problem pulling a small trailer with nothing on it not too long ago. Obviously the big tires don't help, but I would think the 5.4L would be able to handle things like this without sounding like it's going to explode.

 

I tow my fathers 25ft Albemarle and it's about 8,500 pounds fully loaded. I just turn my overdrive off and she pulls pretty good on the highway with 3.55 gears on 33's. My only problem is stopping.

 

As long as you're pushing the O/D off button on the shifter, you're doing fine. Different gears will change RPM at different speeds.

You still didn't mention weight, but 20' bass boat has got to be less than 4000 pounds. Shouldn't have any trouble pulling that.

Please review the suggestions mentioned in the above posts. Those are your best bang for your buck upgrades for your purpose.

 

That 5.4 with 3.55 will sling that 3k boat with no issues.

 

Nobody has asked, but I believe he is running 35" tires

 

Even with 35s pulling a fiberglass bass boat should be bad. But gears would be the simple and best solution.