can I increase my fuel mileage??

I just purchased a 99 EB Expy with the 5.4L a4wd.
was wondering what you guys have done to increase performance and hopefully a bit of fuel economy.

I am getting 13-13.5 right now.
was wondering about a K&N cold air intake. performance chip, and possibly an exhaust.

can you guys that have done them tell me what differences you have seen with the K&N and a performance chip. I am not ready to drop much on exhaust right now.

THANKS!!!!

my advice on fuel economy is this...

if you drive like an old lady, I mean tick-people-off-'cuz-you're-driving-like-Grandma Moses-old-lady.... you'll get better fuel economy

well...I am not far from it now
I just got the thing last week
they guy I got it from had 14.6mpg on the console trip gauge.
I put 1 tankfull in and drove it for the weekend....got 13.6mpg
filled up again on Tuesday morning and I am around 12mpg with burning 1/2 tank.

I have been feathering it pretty light just trying to get the mileage up.

I am running regular gas....
I am going to try plus on next fill up and see if it helps and if its worth the extra money.

I was wondering if K&N cold air intake would be worth the money to help out.
I wouldnt expect to get my money back within the first year....but if it helped starting on year 2 I would probably go for it.

I know you said that you didn't want to drop the big bucks on the exhaust but I did and the acceleration is much smoother now. I didn't purchase a K&N filter but I did buy one of those $40 ones on ebay and it seems to work just fine. Now I don't know much about performance chips. You'll have to let me know about that one. I heard it wasn't reccomended. I don't know the exact gas mileage I'm saving but you can't go wrong with the exhaust. Good luck.

The Expedition is designed to take regular unleaded. Ford recommends you do NOT use premium. Regardless, it will be a waste of money.
I have a 2wd 4.6 and on a 2000 mile trip this week got 19.8. 21.4, and 22.3 mpg on three tankfuls. 75 mph with air used intermittantly and cruise control used religiously. No mods at all.
Cheap gas mileage tip: keep the tires inflated to max as indicated on the tire (not as indicated by Ford).

[c4andk]

Don't use anything but the regular gas, otherwise your car will have horrible hesitation! I tried the plus and supreme and was MISERABLE until that cleared the tank!

[jonmark1985]

So now in my cars i get better mileage with premium. Most of my cars are higher compression (9-1 or 10-1) and i can bump the timing a few degrees with premium.

I've noticed that newer Fords are upping compression again. Even the newer (06) rangers use ~9.5-1 in their 4 cylinder rangers.

Basically when run 89 octane you have to retard the timing back several degrees.

Personally i suggest EXPIREMENTING with premium fuel and keeping an honest tab of your results.

[ChaddyBoy]

I don't have nay figures but I get a huge difference in mileage using Premium over Regular. I have switched back to regular to test my thoery and my mileage has gone downhill. I hadn't heard that Ford doesn't recommend Premium but it won't stop me!

[TBIRD430]

I would do a FULL maintenance sweep 1st. Tranny flush, coolant system flush, front & rear diff fluid change, new fuel filter, Motorcraft plugs & wires, new PCV valve, check air filter, I would get new O2 sensors, and a 2-can Sea Foam fuel system treatment. Heck, u can even add a can of the same Sea Foam to ur crankcase before u change the oil and filter to clean it out too!!! This stuff WORKS and it's cheep!!! Todays fuels are CRAP anyways, build ups are slow and ROB ur engine of power and fuel economy!!! I would also use a name brand gas station REGULARLY like Chevron for example. Keep and eye on ur tires air pressures when cold, and remember this vehicle is an INVESTMENT! So do be weary of keeping ALL these maintenance items up to date. Do a couple at a time, space them out, if it is too much for ur wallet right now. The point is, it will pay off in the end...

After u have done ALL of the above, drive ur SUV for 2 tank fulls and see if there is an improvement. Then go for adding the cold Air intake and cat-back exhaust systems if u plan on keeping this truck for another 3+ years.