I have a 2003, 3.0L with 150k miles and a recently rebuilt automatic transmission. I'm trying to get the best MPG I can right now. One option I was looking at was a performance chip. Specifically a PCR chip. Not really sure if that's the best way to go. I currently run premium every other tank of gas and have been making sure to put in injector cleaner fluid in as well. I'm not sure if there is much else I should or could be doing to improve MPG. Trying to save as much money as possible wherever I can. If I get a jump in performance as well that would be always welcome.

 

If you're using a "Top Tier" gasoline, you're just wasting money on adding fuel injector cleaner.

https://www.toptiergas.com/licensed-brands/


If Ford thought that a "Chip" would improve gas mileage, they would have used one.

If the engine isn't pinging under hard acceleration on regular gas, using premium is a waste of money.


Jack rabbit starts and braking at the last minute are the biggest users of fuel.

 

Welcome to the forum

You are at a bit of a disadvantage using a 3.0l Vulcan engine with an Automatic transmission
Manual transmission is better because you can drive the engine the way it was DESIGNED to be driven

Most V6 engines make their best torque(power) at 2,500-2,800rpm, that's when you can really FEEL the power
3.0l Vulcan makes best torque at 3,600-3,900rpm
It was DESIGNED to be a high RPM engine

But Ford never changed the shift points in the Automatic transmissions to reflect this, so 3.0l Vulcan got the nick name "3.slow", lol

So manually shift, hold it in 2nd gear and see if you can feel the power curve, in 2003 3.0l its at peak torque at 3,900rpm, you should start to feel the power starting to come on around 3,600

So here's the issue, engines don't get best MPG at lower RPMs, idle is 0MPG, lol
They get best MPG just below their peak torque range, engine has just enough power to keep vehicle at speed with gas pedal only down enough to maintain that speed
If you are cruising along at 2,500rpm in a 3.0l then MPG will SUCK, should be 3,100rpm when cruising for best MPG

 

ya thats probably part of the reason then for rate of failure as some quick research when my tranny started failing showed that those 5r55e transmission fail around 150k on average. While the motor can last upwards of 450k plus with regular maintenance. If the transmission fails again, what would the viability of swapping it to a manual be? I can obviously see the main issue of the addition of a clutch as well as cutting out holes for another pedal and shifter along with new wiring or the removal of wiring. Anything else I'm missing and is the cost to convert it similar to rebuilding the auto for a 2nd time?

 

Stock size tires and the correct inflation, new air filter, new fuel filter, and take off from stop signs and stop lights like you have an egg under your gas pedal will also help.