Hello,I will be glad to try and assist you with this,Welcome to Just Answer.
There isn't really any type of program or kit out there that will improve the fuel mileage noticeably on this vehicle to give you better mileage.
The things that will give you the best mileage is making sure your tires are properly inflated,check and replace your engine air filter
once a year.
Avoid performance programs or chips as these can sometimes make the fuel mileage worse.
Driving habits can also make the fuel mileage worse,if you are heavy on the throttle or from stop and go situations this can lower the fuel economy as well.
Your vehicle has a mass air flow sensor under the hood in between the air filter and the engine where the air filter tubing runs.these can become dirty sometimes and can cause inaccurate readings to the computer.YOu can purchase some mass air flow sensor cleaner in a spray can and remove this sensor and spray the cleaner on the internal part of the sensor to clean it,this may give you better mileage if it is dirty.
Make sure the engine stays tuned up as well as the transmission.Service the vehicle regularly.
If you have any failure codes for oxygen sensors you want to make sure these sensors are working properly,if one or more of these are faulty then this will also give you bad fuel mileage.
I always recommend to replace these sensors around 100,000 miles to keep the engine running properly and for better fuel consumption as these can start to read incorrectly.
All of these things here will give you the best fuel economy for your vehicle.
Let me know if you need anything else,click accept if you feel satisfied with your answer as this is how I get credited for my time,Thanks Pete!