I have an 03 expedition withe the 5.4L triton and 113,000 miles. Im getting into motorcycle racing and want to get a small toy hauler (6-7000lbs loaded). The truck is rated for 9000lbs but my current trailer probably weighs 3800 loaded and I hate hearing the motor scream through the mountains without the acceleration to match. A superduty is in the plans but a few years down the line. I was thinking about getting a super chip programmer, trying to bolt on the 04's 32v head for the extra 40hp and putting the F250 gears in the rear. What suggestions do yall have?

I have a K&N intake that whistles like a turbo (suprisingly) and a magnaflow exhaust so I think its breathing rather well.

 

If you are looking into a tuner the best thing I could recommend would be the Hypertech Max Energy programmer. I have one and I am very happy with it. You can tune individual shift points, rev limiter, top speed limiter, shift firmness, idle speed. You also can recalibrate the speedo if you have different tire sizes or different rear diff gear ratios. You can also choose between regular and premium fuel. I would also change the plugs if you haven't already. I changed mine to E3 plugs and I noticed a big difference in power and throttle response. Depending on how long you want to keep the truck you can switch out the rear diff but make sure you are getting the correct size, there are two different sizes, I cant remember them off the top of my head. Some people have used throttle body spacers, I am not sure if they work or not but many people say they do, that's your decision. As far as swapping the heads like you said, I don't think they fit perfectly but I could be wrong. I wouldn't tear the engine apart if I was you just because you are not going to keep it that long so it may not be worth it. I would try the smaller things first and see what happens.

 

I TOW A 20' BOX WITH A 03 F150 5.4L 4X4. IT HAD 3.55 AND I SWITCHED THEM OUT TO 4.10. IT TOWS MUCH BETTER, BUT IT STILL SCREAMS. IT IS ALL STOCK, BUT IT GOES MUCH EASIER NOW.

 

If I could get the power where i want I will keep the truck until the wheels fall off and then get the superduty. I just feel that when the motor screams at like 3500 and doesnt really accelerate meaningfully that Im doing more harm than good. Now I will add that when towing the trailer previously I had my 22's on with fairly meaty tires. Becuase of our back to back blizzards I put the factory wheels back on so I may see a difference but I doubt it because the mpg's are about the same.

 

There are several things to check before modding it further. Spark plugs and fuel filter for sure. Keep the K&N filter clean, and also make sure the MAF senor filaments are clean along with the throttle body.

I would ditch the 22's as well, at least for long tows through the hills. If the Expy isn't equipped with the towing package, a tranny cooler should be top priority.

 

Sorry it does have the tow package. Class IV hitch with 7 and 4 pin connectors, tranny cooler and oversize radiator.

 

^ Cool. What kinda gears are in the axle? 4x4?

 

The internet says 3.73

 

Yeah, the '03 Expy I've been around used 3.73's too.

Take a look at those items I listed, and see how they look. It's going to hold a lower gear when climbing hills, and as long as that's kept to a minimum, you should be fine.

 

So I talked with a few people today one of which works at Ford in service and they tell me that all the gasoline engines will scream with that weight in the mountains regardless of the gears. Is this true?

Why did Ford only have 3 valves per cylinder on my year 5.4 but 4 valves per cylinder on the 04's and up? They are both 330

 

Also are there tranny coolers that are better than others? Mine is the factory one with the tow package.

 

'97-'04 Expedition 5.4's had 2V/cylinder. '05+ has 3V/cylinder

 

My mistake. Why 2V/cylinder or even 3 instead of 4?

 

If you want a 4-vavle engine look at the 1st gen Navigators.

 

Do what I did buy an Excursion.